Adderall is an amphetamine-based drug that is primarily used to treat attention deficit hyperactivity disorder (ADHD). It’s used to increase concentration, working memory and to promote alertness. Adderall is also commonly misused as a study drug by students and young professionals seeking increased cognitive abilities with the ultimate aim of better productivity.

The typical dose can be anywhere between 2.5 – 60 mg daily and is given 1-3 times a day.

Under the Misuse of Drugs Act 1971, it is not an offence to consume or be under the influence of any controlled substances in the UK. However, possession and supply are both criminalised. The only instance in which it is not a criminal offence to possess Adderall is when you are prescribed the drug for medical purposes.

In the UK, Adderall is a class B substance. Penalties for unlawful possession and supply can potentially be 5 years in prison and/or an unlimited fine, and up to 14 years in prison and/or an unlimited fine respectively.

In the US, Adderall is licenced as a medication to treat ADHD and narcolepsy. However, it is not licenced in the UK. Although it is occasionally prescribed, this is not common practise under the NHS.

Adderall is taken in the form of a pill, usually either blue or orange. The extended-release version comes in a capsule.

Adderall is consumed by oral ingestion. Its duration is between 4 -6 hours and peaks at around 90 minutes.

It is typically available in tablets of 5mg, 7.5mg, 10mg, 12.5mg, 15mg, 20mg and 30mg strengths. It may also come in the form of an extended-release tablet of identical doses.

Adderall is a chemical compound that is made up of powerful blends of the amphetamine salts dextroamphetamine and levoamphetamine, which are isomers of the original amphetamine molecule and come in a 3:1 ratio. The blend consists of the following: One-quarter racemic (d,l-)amphetamine aspartate monohydrate, one-quarter dextroamphetamine saccharin, one-quarter dextroamphetamine sulfate, and one-quarter racemic (d,l-)amphetamine sulfate

Adderall is an amphetamine-based drug. Amphetamines exert their pharmacologic action by blocking the reuptake of noradrenaline (NA) and dopamine into presynaptic neurons, increasing the release of these into the extraneuronal space. Dextroamphetamine, acts peripherally by release and reuptake inhibition of the neurotransmitter’s acetylcholine and histamine but not glutamate via the VMAT2 transporter. Amphetamines release stores of NA and dopamine from nerve endings by opening the respective channels.

Amphetamines also release stores of serotonin from synaptic vesicles. Like methylphenidate (Ritalin), amphetamines prevent the transporters for dopamine and NA from recycling them. These combined effects rapidly increase concentrations of dopamine and NA in the synaptic cleft, promoting nerve impulse transmission in neurons that have those receptors.

Physiologically, Adderall increases bothheart rate and blood pressure. For most people however, these effects are modest.

Adderall is detectable in the body following a number of different types of drug tests. The length of time that they are detectable for does, however, vary from test to test.

  • In the blood, Adderall is detectable up to 46 hours after use.
  • In urine, it is detectable for 72 hours after use.
  • In saliva, it is detectable for 20 to 50 hours after use.
  • In hair, it is detectable up to 3 months after use.

Adderall primarily works to increase concentration and general cognition. These effects are much greater in those with ADHD. There is evidence that Adderall can lead to improvement in attention performance, working memory and inhibitory control in healthy adults. A number of studies have demonstrated Adderall’s ability to enhance the cognition of adults with tests of problem solving and executive function. However, these effects are generally found to be quite modest.

The effects of Adderall reach can be observed anywhere between 30 to 60 minutes after ingestion, and the peak concentration in the blood occurs at around 3 hours post-ingestion. The effects will last for between 4 and 6 hours for instant release, and around 8 hours for extended-release tablets.

Adderall is primarily used to treat attention deficit hyperactivity disorder (ADHD). ADHD is a common neurobehavioral disorder affecting between 3 and 7 per cent of school-aged children. In the majority of cases, ADHD persists into adulthood.

The disorder results in delayed learning ability, impaired academic achievement and delayed maturation. Symptoms commonly include having trouble concentrating or completing simple of complex tasks, forgetfulness, hyperactivity, being easily distracted, impulsive behaviour and the inability to get along with others.

Although it is rarely prescribed in the UK, its use for the treatment of ADHD in the US is widespread.

Short-term physiological effects include:

  • Decreased appetite
  • Involutory body movements
  • Hyperactivity
  • Jitteriness
  • Nausea
  • Itchy skin
  • Irregular heart rate
  • Hypertension
  • Headaches

Possible long-term physiological effects:

  • Weight loss
  • Decreased appetite
  • Cardiomyopathy
  • Heart palpitation
  • Tachycardia
  • Elevated blood pressure
  • Fatigue

Possible adverse psychological reactions:

  • Anxiety
  • Depression
  • Mood swings
  • Psychosis
  • Aggression
  • Sleep difficulties
  • Paranoia
  • Hallucinations

To mitigate these risks, users should firstly speak to a medical professional before using Adderall. It will also be important to begin on a low dose to avoid unnecessary over-consumption of the drug. Lastly, users try to minimise the time which they are taking the drug, in order to avoid the potential of addiction and developing long-term adverse effects.

Adderall should not be used in persons who have not tried other psychotherapy before, have high blood pressure or any form of heart disease, are very nervous or have severe insomnia, have a history of addiction to drugs or alcohol, take monoamine oxidase inhibitors, or have Tourette syndrome, which is one of several chronic tic disorders

Generally, the combination of drugs should be avoided as much as possible unless specifically prescribed by a medical professional. See this chart for an overview of drug interaction of a wide range of illegal and legal drugs.

With Adderall, the use of stimulants should be avoided. This is because Adderall is also a stimulant, and by combing it with another, it can exacerbate the potential for severe physiological and psychological adverse reactions.

The use of Adderall should also be avoided when taken in conjunction with the following substances, as it may lead to additional, severe harms:

  • Duloxetine
  • Levothyroxine
  • Escitalopram
  • Omeprazole
  • Tramadol
  • Monoamine oxidase inhibitors (MAOIs)

Alcohol and Adderall

When taking Adderall, users should avoid the intake of alcohol. Adderall is a stimulant, whilst alcohol is a depressant. This means that the two drugs work to counteract each other. As a result, users might feel the need to take additional doses of each drug to obtain their desired effect. This could lead to increased adverse reactions. By drinking alcohol alongside taking Adderall, the negative symptoms of both drugs will also be exacerbated.

Like other amphetamines, users of Adderall can develop an addiction to the drug. This can also result in withdrawal symptoms such as paranoia, depression, difficulty breathing, dysphoria, gastric fluctuations and tiredness. These symptoms lead chronic users to re-dose frequently and as such increase the possibility of addiction. Someone who has a dependency on Adderall should never stop taking the drug abruptly, and instead needs to do so gradually and under medical supervision.

It is not harmful because it is produced by pharmaceutical companies.

Research has shown that users of Adderall and similar substances do not consider it to be physically or psychologically harmful due to them being associated with instrumental pursuits of academic and productivity-related goals. This belief also stems from the fact that Adderall is produced, regulated and prescribed by the medical establishment.

This is, however, a myth. Adderall can produce serious adverse effects such as various cardiovascular events, worsening mental illness, and even increase the risk of sudden death.


It is only a stiff cup of coffee.

Many users believe that Adderall is nothing more than a stiff cup of caffeinated-coffee. However, the drugs’ composites are much more serious than caffeine. Adderall is composed of different amphetamine salts that increase extracellular levels of dopamine, serotonin and noradrenaline. This myth is problematic because it minimises the seriousness of potential adverse reactions to Adderall.


It makes you smarter.

It is commonly believed that, by taking Adderall, the user can become instantly smarter. There is evidence that healthy adults may receive small to moderate cognitive benefits in the areas of working memory, response inhibition and processing speed. However, these effects do not automatically make the user smarter, but instead simply complement existing cognitive abilities. Furthermore, a lot of studies have found that these beneficial cognitive effects are only very modest. In fact, there is evidence that argues to the contrary, demonstrating that stimulant misuse is negatively correlated with academic functioning.


If the user finds Adderall to be helpful, then they must have ADHD.

As Adderall is primarily used to treat ADHD, users commonly believe that if they take Adderall and benefit from it in some way, then they must have ADHD. However, this occurs due to a misunderstanding as to what ADHD actually is. The disorder is often trivialised to being nothing more than the periodic inability to concentrate. ADHD is a lot more complicated than this however, and is additionality characterised by impulses and continual restlessness.

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chemical structure of phencyclidine (PCP) molecule

PCP stands for phencyclidine or phenylcyclohexyl piperidine, and is a dissociative anaesthetic (similar to ketamine) causing a wide range of effects including hallucinations, feelings of euphoria, and of being disconnected from one’s environment. Street names include angel dust, hog, and peace pills.

PCP was discovered in 1926 and was marketed as a general anaesthetic from the 1950s. It was limited to veterinary use in 1967 due to side effects in humans such as dysphoria, hallucinations and poor muscle relaxation. Veterinary use was also suspended in 1978 after the discovery of ketamine

Illegal production of PCP began in the 1960s and it emerged as a recreational drug. Recreational use became more widespread throughout the 1970s but has become less common since.

PCP can be found as an oil, liquid, powder, pill or crystal. It is most commonly smoked, often mixed with cannabis or tobacco, but can also be insufflated (snorted), taken orally (as a pill or powder), or injected.

When smoked with cannabis or tobacco, the usual dosage is 1-10mg of PCP, while tablets usually contain between 1-6mg. When taken orally or inhaled, 10mg of PCP can produce sedation, whereas when injected only 0.25mg is needed.

Taking PCP by injection is strongly advised against. This is because very low doses are required to cause effects meaning there is a higher risk of overdose.

As production is unregulated, it is difficult to know the exact dose being taken. There is also a poor relationship between PCP intoxication and the blood serum concentration of PCP in patients, meaning we have a limited understanding of safe doses of PCP. It is thought that doses greater than 10mg usually result in mild coma and doses of 25mg or more can result in deep coma, convulsions and even death.

PCP action is not entirely understood but is thought that it mainly acts as an N-methyl-D-aspartate (NMDA) receptor antagonist, meaning the drug blocks the action of glutamate at NMDA receptors. PCP also stimulates an enzyme called tyrosine hydroxylase resulting in an increase in dopamine, norepinephrine and serotonin production. Dopamine and serotonin production is associated with many other hallucinogenic drugs and could be responsible for the hallucinations and euphoria caused by PCP. At high PCP doses, strong NMDA antagonism results in complete analgesia and anaesthesia.

The effects, onset time and duration are dependent on the dose taken and the route of administration.


Onset time:

Effects are usually felt anywhere between 15-60 minutes after oral consumption, but are felt just 2-5 minutes after inhalation.



The effects of PCP usually last between 6 and 24 hours but could be up to 48 hours.



The effects of PCP are numerous and highly variable but are often summarised using the mnemonic RED DANES: rage, erythema (red skin), dilated pupils, delusions, amnesia, nystagmus (uncontrolled lateral eye movements), excitation and skin dryness. Effects may vary depending on dosage.


Low doses (2-5mg, orally ingested):

  • Euphoria
  • Hallucinations
  • Dissociation – feeling of detachment from your body/surroundings
  • Sadness, anxiety, paranoia, confusion – often felt in waves
  • Numbness – as the analgesic effects begin
  • Unpredictable behaviour
  • Aggressive or violent behaviour
  • Reduced pain sensation


Moderate to high doses (5-25mg, orally ingested):

  • Confusion
  • Further reduced pain sensation
  • Stupor
  • Mild coma – often occurs at doses greater than 10mg


Very high doses (>25mg, orally ingested)

  • Convulsions – uncontrolled shaking
  • Deep coma with no response to pain
  • Death – can be caused by complications as a result of inhibited pain response (e.g. burns or drowning in a bath), violent behaviour, hyperthermia, hypothermia (e.g. falling asleep outdoors in cold weather), and breathing problems


Comedown: Some users may feel a comedown as the drug wears off. This may last for around 24 hours and feels similar to a hangover. Symptoms can include nausea, headaches and trouble sleeping.



Chronic users can develop a higher tolerance to PCP with frequent use, meaning that they need increasingly higher doses to experience the same effects.

Since the use of PCP as a medical anaesthetic for humans was replaced with Ketamine in 1965, and then later for animals, there have been no reported medicinal uses of PCP.

Some of the effects of PCP can have dangerous consequences, resulting in long-lasting mental effects, physical injury or even death. Although these usually only occur at high doses, it is important to know the risks.


Risks include:

  • Analgesia (loss of pain sensation)
    • This can lead users to hurt themselves, either intentionally or without knowing, and may mean that they do not seek appropriate help for an injury.
  • Violent/unpredictable behaviour
    • Violent behaviour is often reported in people intoxicated with PCP, and is one of the leading causes of death.
  • Cardiovascular effects
    • PCP can cause hypertension (high blood pressure) and tachycardia (fast heart rate). These are usually mild but can be severe in rare cases, and cardiac arrest has been reported following PCP intoxication.
  • Kidney damage
    • Rhabdomyolysis is seen in roughly 2.5% of people admitted to hospital with PCP intoxication. This is when myoglobin is released from the muscles into the blood stream causing damage to the kidneys, or even kidney failure.
    • The exact causes are unknown but could occur as a result of intense muscle contractions caused by PCP or due to PCP acting directly at the muscles.
    • Rhabdomyolysis can be identified by dark, reddish urine and sore or weak muscles and requires immediate medical attention.
  • Overdose
    • As previously mentioned, we have a poor understanding of safe PCP limits but it is suspected that doses exceeding 25mg can constitute an overdose.
    • Symptoms of an overdose include: agitation, nystagmus (uncontrolled side-to-side eye movements), prolonged coma, hypersalivation, hypertension, convulsions, opisthotonos (muscle spasms causing arching of the back and neck), respiratory depression and catatonia (awake but unresponsive).
    • Immediate medical attention is required if a PCP overdose is suspected.

Long term mental effects of PCP use include:

  • Chronic use can lead to acute anxiety, depression and psychosis.
  • Toxic Psychosis
    • Some PCP users experience psychosis after the effects of PCP have worn off. This can involve hallucinations, paranoid delusions and delusions of influence or religious grandiosity.
    • These symptoms often disappear after a few days but can last from weeks to months, requiring treatment. A psychotic state lasting for more than 2 months may indicate that a pre-existing psychosis has been exacerbated.
    • Schizophrenic-like syndromes have been reported in PCP users after chronic low-dose use as well as after single use.
  • Users have also experienced symptoms of frontal lobe syndrome such as speech impediments and memory loss long after taking PCP, as well as ‘flashbacks’, which is when users experience the feeling of being on PCP long after the drug has worn off.
  • PCP can cause changes in NMDA binding in the hippocampus that remain after PCP use. This may be responsible for altered speech and memory, and psychosis.

As PCP has a sedative effect, it should never be mixed with other depressants, such as alcohol, benzodiazepines or opioids, as this can increase risk of coma. Mixing with depressants can also lower your heart rate and breathing to dangerously low levels.

PCP can be addictive. Chronic users may find it difficult to give up and can develop a higher tolerance to PCP with frequent use meaning that they need increasingly higher doses to experience the same effects.

Addicts may also experience withdrawal symptoms when they stop taking the drug. Short-term withdrawal symptoms include high body temperature, seizures, agitation, muscle twitching and hallucinations. These effects can appear a while after the PCP wears off as the drug can remain in the body for around eight days. Long-term withdrawal symptoms may include depression, memory loss, cognitive dysfunction, impaired speech and weight loss.

We know little about whether any health conditions could make PCP more dangerous. However, there are a few pre-existing conditions that are suspected to increase the risk of some of the more dangerous effects of PCP.

It is suspected that a pre-existing psychotic disorder may increase the likelihood of toxic psychosis following PCP intoxication. It is also possible that other mental health conditions such as anxiety or depression could be exacerbated by PCP use. It has also been suggested that being prone to aggression could make PCP users more likely to exhibit violent behaviour while on PCP. Youth previous psychiatric problems may also be risk factors.

Little is known about whether pre-existing conditions of the cardiovascular system (e.g. high blood pressure, arrhythmias) can make PCP more dangerous. However as PCP is a cardiac irritant, users with conditions that put them at increased risk of cardiovascular problems should be cautious of using the drug.

PCP is classified as a Class A drug under the UK Misuse of Drugs Act and as Schedule II under the United States Controlled Substance Act. This means it is illegal to possess, supply or produce PCP in the UK and USA.

Low doses

PCP gets more dangerous with higher doses. Doses of less than 5mg are considered low and tend not to produce most of the more dangerous symptoms.


Sober sitter

The dissociation, hallucinations and delusions caused by PCP can be confusing. Taking PCP with a sober sitter present, rather than alone, can help users to maintain their grip on reality and manage dangerous or unpredictable behaviour.



PCP can cause unpredictable and potentially violent behaviour, and the loss of pain sensation can cause users to injure themselves. Staying in a safe and familiar environment, away from things that might cause injury can reduce the chance of harm.


Don’t combine with sedatives or depressants

As PCP can have sedative effects, combining with other sedative or depressants (e.g. alcohol, benzodiazepines, opioids) can increase risk of coma and cause depressed breathing and heart rate.


Know the signs of overdose

Symptoms of an overdose include: agitation, nystagmus (uncontrolled side-to-side eye movements), prolonged coma, hypersalivation, hypertension, convulsions, opisthotonos (muscle spasms causing arching of the back and neck), respiratory depression and catatonia (awake but unresponsive). If you recognise any of these in yourself or someone else, seek medical attention.


Stay hydrated

PCP can cause increased body temperature. Dehydration can be avoided by drinking water.


Don’t inject PCP

When taken by injection, very low PCP doses are required to cause effects meaning there is a much higher risk of overdose.


Don’t use often

Some of the more dangerous or long-lasting side effects of PCP become more common with frequent use.

PCP makes people violent

Violent behaviour is often associated with PCP use however the actual prevalence of PCP-induced violence is debated.

Many who disagree with the idea that PCP makes people violent point out that the majority of research into PCP and violence works with PCP users who have been incarcerated or hospitalized and could only represent the more extreme examples of PCP abuse. Additionally, when PCP users in the general population are studied, many authors agree that violence in PCP users is much less common than is portrayed in the media.

Some people also suggest that only certain risk factors cause PCP users to become violent while intoxicated. McCardle and Fishbein found that PCP users who exhibit violent behaviour tend to be younger, have more psychiatric hospitalizations and are generally more aggressive whether intoxicated or not.

There is limited research that investigates the connection between PCP use and violence, and studies often have methodological weaknesses and produce contradictory findings. Therefore we cannot determine the extent to which PCP induces or exacerbates violent behaviour and it is worth considering that this is still a possibility when taking the drug.

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chemical structure/skeleton of modafinil molecule

Modafinil (2-[(diphenylmethyl) sulfinyl] acetamide) is a manufactured drug that is a Prescription Only Medicine in the UK. It is available on prescription for a number of sleep disorders, such as narcolepsy. Although it is legal to possess, supply is illegal without prescription.

Modafinil has also become increasingly used as a recreational drug. Many students and professionals use the drug to improve their productivity and focus, as well as staying awake for longer. It has therefore been likened to drugs such as Adderall, Vyvanese and Ritalin which have also been used recreationally by healthy individuals to improve concentration.

Modafinil comes in the form of a white tablet. Typically, the drug comes in dosages of either 100mg or 200mg. The suggested daily dose for the treatment of narcolepsy is between 100-400mg.

The majority of recreational users report using 200mg as their preferred dose, with a few using up to 400mg, and some excessive dosages being 1000mg and over.

Modafinil is now off-patent and is available with a number of licensed ‘branded generics’ with their own trade names. Provigil is the main UK trade name, but modafinil is also available worldwide with a range of trade names such as Modalert, Alertec and Modavigil.

Armodafinil is a stereoismer of modafinil and is often marketed alongside or in replacement of modafinil. They have similar effects and are taken at similar dosages.

Modafinil is a stimulant. The exact way in which modafinil works in the brain is still relatively unknown as it has a complex mechanism of action. However, it is known that it acts on a number of neurotransmitters. It has been shown that modafinil works primarily through noradrenaline and dopamine transporter inhibition. It also acts on serotonin, histamine, gamma-aminobutyric acid and glutamate. Increases in the hypothalamic release of histamine also occurs as a result of modafinil’s action on the orexin system.

Physiologically, modafinil increases blood pressure and resting heart rate.

The onset time of the effects of modafinil can be anywhere between 30 and 90 minutes. The effects reach its peak between 2 and 4 hours after ingestion and can last between 12 and 15 hours. The main effects have been likened to a very high dose of caffeine. It is reported to improve concentration, decision-making and planning, whilst dramatically reducing tiredness.

As it is a stimulant, users of modafinil can experience similar adverse effects to other stimulants. These can include:

  • insomnia
  • headache
  • paranoia
  • irritability
  • stomach aches
  • loss of appetite
  • nausea
  • diarrhoea
  • weight loss
  • blurred vision
  • dizziness

In rare cases, a high dose of modafinil can also cause psychosis.

However, despite its pharmacological similarity to other stimulants, it has been reported that these effects are not as serious as other stimulants.

Modafinil has been used to treat narcolepsy since the 1980s. Narcolepsy is a sleep disorder that is characterised by excessive daytime sleepiness. Unlike with other stimulants  the use of modafinil doesn’t seem to lead to rebound (hyper) sleepiness when stopped.

Nowadays, it is primarily used as a cognitive enhancer, but has also been used by the military and those who have sleeping problems due to irregular work shifts.

There is also an emerging body of evidence of its usefulness in treating cocaine addiction.

Lastly, it has been shown that modafinil could be useful in treating disease-related fatigue, attention-deficit disorder, Alzheimer’s disease, age-related memory decline, depression, idiopathic hypersomnia, cognitive impairment in schizophrenia and myotonic dystrophy. However, evidence for its usefulness in treating these disorders is not yet significant enough to warrant its widespread use for them.

Modafinil has a half-life of 12 -15 hours, with the drugs main effects peaking at around 2 – 4 hours and then lasting for around 12 hours or more. Therefore, if a user experiences adverse side-effects, it can be particularly uncomfortable as these are likely to last for a long duration.

As it is a sleep-inhibiter, users can also experience sleep insomnia. Prolonged periods of sleeplessness can cause increased stress and will impair immune functions. It can also increase the risk of cardiovascular disease, diabetes, metabolic syndrome and depression. There is also a link between sleep deprivation and bacterial infections in the blood because of dampened immune responses.

The possibility of addiction to modafinil has been doubted by some with only a few cases having been reported.

However, because modafinil acts on neurotransmitters such as dopamine, it has been suggested that addiction is possible with modafinil because of its mood-altering effects.

There have also been a few reports of users experiencing withdrawal symptoms such as poor concentration, sleepiness, low energy, depression, anxiety and shortness of breath. These are, however, rare and in most cases very mild.

Not much is known about the long-term effects of modafinil. However, it has been demonstrated that prolific and prolonged use of the drug could cause serious disruptions to the users sleep architecture.

It has also been shown to have the effect of increasing dopamine in the brain, which contributes to abnormal dopamine function when not taking the drug. This could have long-term implications by increasing the potential for the drug to be abused by vulnerable users.

These long-term effects can also occur when high doses are used regularly.

Mental Health

Modafinil can cause anxiety, paranoia and jitteriness. Because of this, those with mental health issues such as anxiety, depression or a history of psychosis should be extremely cautious when using it.


As the effects of modafinil can last for over 12 hours, any adverse effects might last a long time and so can become particularly uncomfortable and harmful. It is therefore a good idea to start with a low dose to get a better idea of the level of the users’ tolerance.

Oral Contraception

It has been shown that modafinil can reduce the effectiveness of the oral contraceptive pill. This reduced effect can also last 1-2 months after taking modafinil.


Modafinil can also cause a decrease in appetite. Users should therefore ensure they are eating consistently throughout the day, and it is especially important that you are keeping well hydrated because dehydration can cause loss of strength, stamina and the exacerbation of common symptoms of stimulants such as anxiety, headaches, jitteriness and dizziness.


In order to counter the possible effect of insomnia, it is best to take modafinil at least 8 to 10 hours before the user plans on sleeping to ensure the main effects have sufficiently worn off.


It is also illegal to supply modafinil without a prescription. However, many sellers advertise modafinil for sale without a prescription. These sellers are unregulated and so it is not possible to guarantee that it will definitely be modafinil that is being sold. As a result, users should always test their drugs before using them.

‘It can make you smarter’

Modafinil cannot make the user smarter. In the last decade, many students and working professionals have started to use the drug to increase the amount of work they are able to complete.

There is some evidence that it increases working memory, the users’ ability to plan and to concentrate better, however this does not mean you will automatically become smarter. In fact, some users have reported that instead of having increased concentration on their work, they instead concentrate on certain distractions like watching videos or using social media and struggle to get back to concentrating on what they intended to do.

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Chemical structure of 2CB molecule

2C-B stands for 2,5-dimethoxy-4-bromophenethylamine, a synthetic drug with psychedelic effects. 2C-B is a phenylethylamine derivative and has a similar structure to mescaline, another psychedelic drug. It is described as a psychedelic drug with visual effects and some stimulant-like properties. Anecdotal reports draw similarities between LSD and MDMA.

2C-B was first synthesised by Alexander Shulgin in 1974 and his findings were reported in his 1991 book entitled PiHKAL. Following its discovery, there was some reported use of 2C-B by psychotherapists in the 1970s, which was followed by a breakthrough of use into the recreational drug scene in the 70s and 80s. 2C-B had a short-lived legitimate history and was marketed as an aphrodisiac in smart shops in America and the Netherlands, before being classified as illegal in several countries, including the UK, in the 90s.

Currently, 2C-B (and other 2C drugs such as 2C-D, 2C-E, 2C-I, 2C-P) are Class A, Schedule 1 drugs in the UK. This means they are illegal to possess, supply and produce. In recent years, 2C-B has increased in popularity in sales over the darknet, and is popular in the rave and festival scene.

2C-B is typically found as a powder (often white crystals), pill or in a capsule. These are typically taken orally and the standard oral dose is between 15-25 mg.

2C-B can also be insufflated (snorted), although this carries increased risk because the dosage required to achieve active effects is much lower than an oral dose. There are anecdotal reports of pain when snorting 2C-B.

We strongly advise against nasal insufflation of 2C-B

There is still very limited research into the mechanisms of action of 2C-B in the human brain and body. However, it is suggested that 5-HT2 and α-adrenergic receptors are involved. The 5-HT2A receptor is associated with classical psychedelics, including LSD and psilocybin, whereby the drug binds and act as agonists. There is conflicting evidence concerning the mechanism of action of 2C-B, as some research suggests that 2C-B acts as a partial agonist at the 5-HT2A receptor, whilst other research suggests that 2C-B acts as an antagonist at the 5-HT2A receptor. It has also been suggested that the 5-HT2C receptor may be involved in the response activated and that the α1-adrenergic receptor is responsible for the stimulant effects.

The onset time of 2C-B is typically between 45-75 minutes after oral consumption. A ‘come up’ period with a duration of 15-30 minutes is commonly described and can include feelings of anticipation and anxiety, as well as bodily sensations including tingling and pins and needles.

Although there are anecdotal reports of the effects of 2C-B, recent observational studies have provided valuable insight into the emotional and pharmacological effects of 2C-B. The effects of 2C-B are heavily dose-dependent and typically include:

  • Enhanced mood and feelings of euphoria
  • Laughter
  • Visual and auditory alterations and hallucinations
  • Enhanced energy
  • Sexual arousal/enhanced libido
  • Nausea, vomiting and diarrhoea

After the synthesis of 2C-B by Alexander Shulgin in 1974, there were reports that he recommended its use in therapy to a limited number of psychotherapists due to the empathogenic effects of 2C-B.

There is very limited clinical research into the medical uses of 2CB, however an observational study showed that 2C-B acts as an entactogenic drug. Entactogens have effects which include emotional openness, oneness and introspection. MDMA is also described as an entactogen and this property is attributed to its potential use as a tool in psychotherapy for several psychiatric conditions, including PTSD. Therefore, it has been suggested by some that 2C-B may pose the therapeutic benefit that Alexander Shulgin had claimed.

2C-B induces a psychedelic experience including alterations to mood, as well as visual and auditory hallucinations. The nature of a 2C-B trip can be emotionally challenging for some people, inducing states of anxiety and paranoia. Similar to all psychedelics, the psychological risks can be minimised by ‘set and setting’, ensuring that both your mind-set is stable and well prepared, and that the environment is comfortable and safe.

Anecdotal reports suggest that recreational doses of 2C-B are associated with low toxicity and are physiologically well tolerated. However, there is a lack of scientific studies on the toxicity and long-term effects of 2C-B. A recent observational study investigated the immediate pharmacological effects of 2CB, demonstrating increased heart rate and blood pressure after 2CB consumption. Therefore, 2C-B may be dangerous for those with heart conditions.

The dosage of 2C-B is in the milligram region and the effects are highly dose dependent. There is a very steep dose response curve, which means that small changes to the dose that may be undetectable by eye could have drastic effects on the 2C-B experience. Alexander Shulgin states in PiHKAL that “over the 12 to 24 milligram range, every 2 milligrams can make a profound increase or change of response.” Therefore, it is critical that doses are measured accurately.

Snorting of 2C-B is highly inadvisable and there are anecdotal reports of pain associated with insufflation. Extra caution is required with snorting as the dose required is much smaller than an oral dose and the onset is very rapid, often within minutes.

2C-B can be tested using the Marquis Reagent (NIK® test A) and will produce a yellow/green colour. However, extra caution is needed as 2C-I (another 2C drug with different effects) will also give a yellow/green colour using the Marquis Reagent (NIK® test A). There are other drug testing kits available that can be used for further clarification of substances, but it is important to appreciate the limitations in determining the differences between the 2C series of drugs which includes 2C-B, 2C-D, 2C-E, 2C-I, and 2C-P.

Read more about 2C-B harm reduction here.

Similar to other psychedelic drugs, a history of mental health illness (such as schizophrenia, psychosis or bipolar disorder) may increase the likelihood of an unpleasant experience (‘bad trip’) and there is the risk 2C-B may exacerbate these conditions. However, there is still a very limited understanding of the dangers associated with the use of psychedelics in those with pre-existing mental health conditions. There has been a report of psychosis after 2C-B, however it is important to state that the purity of the 2C-B was not confirmed in this case.

2C-B increases heart rate and blood pressure. These effects could be more dangerous for those with a history of heart conditions or high blood pressure. Some have suggested that 2C-B may present more risks for those with diabetes or epilepsy.

It is important to understand the metabolism of 2C-B by the body and the potential implications this may have. 2C-B is metabolised by enzymes called monoamine oxidases (MAOs) A and B, and therefore this could pose a risk for those on Monoamine Oxidase Inhibitors (MAOIs).

Prescription drugs with an associated risk:

  • MAOIs (some antidepressants)
  • Tramadol
  • Antipsychotics
  • Antihypertensives
  • Central nervous system depressants
  • Vasodilators

2C-B should not be consumed with alcohol or other drugs. An understanding of the effects and mechanisms of 2C-B can provide insight into the risks associated with mixing 2C-B with other drugs.

Key drug combinations to avoid are listed below:

• 2C-B should not be mixed with tramadol due to the increased risk of seizure

• 2C-B should not be mixed with ayahuasca or ‘changa’ as they both contain MAOIs

• 2C-B should not be mixed with other stimulants including cocaine and amphetamines

• 2C-B should not be mixed with cannabis

• 2C-B should not be mixed with other psychedelics as this carries the risk of making the trip more intense

• 2C-B should not be mixed with any recreationally used prescription drugs that are known to potentially interact with 2C-B. This includes all those listed here.

2C-B addiction is unlikely because 2C-B is considered to have a low potential for addiction, similar to other psychedelic drugs.

2C-B produces a psychedelic experience with some stimulant-like properties. Informed harm reduction advice can help to mitigate some of the associated risks.

Being educated and prepared

It is important that you fully educate yourself on the health risks and drug interactions associated with 2C-B, and ensure that an accurate and suitable dose is consumed. 2C-B has some stimulant properties and therefore it is important to remain hydrated, especially if dancing.

Set and setting

‘Set’ refers to a person’s mind-set including their mood, thoughts and expectations. This can have a significant effect on the experience of the trip and therefore it is advised that 2C-B is only consumed when a person is in a positive and stable state of mind. ‘Setting’ refers to the environment and social situation in which the drug is consumed. Although some consider 2C-B a milder psychedelic, it is advisable that it is consumed in a safe and familiar environment.


The presence of a sober sitter is recommended for those with limited experience of psychedelic drugs. The sitter can provide reassurance and support during and after the trip.

Other 2C drugs

2C-B is part of the 2C family of psychedelic phenethylamines, many of which were originally synthesised by Alexander Shulgin. Other popular 2C drugs include 2C-D, 2C-E, 2C-I and 2C-P. However, the effects of each 2C drug will vary and education of the differences is recommended before consumption of other 2C drugs.

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Chemical structure of DMT (N,N-Dimethyltryptamine) molecule. DMT is a psychedelic drug

DMT stands for N, N-Dimethyltryptamine. It is a powerful psychedelic drug, with serotonergic effects on the human brain, which can induce a rapid and intense psychedelic experience, often referred to as a ‘DMT trip’. The DMT experience is usually characterised by visual hallucinations, frequently involving powerful entities, and is often associated with deeper meaning. This meaningful experience is sometimes called a ‘DMT breakthrough’. When used as a recreational drug, DMT can be smoked, snorted, or injected in its crystal form.

The DMT molecule is structurally similar to other psychedelic tryptamines such as 4-AcO-DMT, 5-MeO-DMT, and psilocybin, allowing it to bind to serotonin receptors and induce psychedelic effects.

DMT is found naturally in a variety of plants and has a long history as the psychoactive component in ayahuasca, a thick hallucinogenic tea, which is considered an important element of shamanic tradition in the Upper and Lower Amazon.

Currently, there is limited evidence supporting endogenous DMT production in humans, specifically whether DMT is produced in the brain.

This information page will focus specifically on DMT rather than ayahuasca, for more information on ayahuasca please click here.

DMT comes in various forms, which are suitable for different methods of consumption and will alter the duration of the experience. Pure DMT is a white crystalline powder or solid, but it is more commonly found as a yellow-pink powder or solid. It can also be found in herbal mixtures called ‘changa’.

  1. Smoked (DMT): DMT powder can be smoked in a pipe or bong, or vaporized including through the use of vape pens. Freebase DMT is typically associated with smoking.
  2. Smoked (Changa): Changa is an herb mixture containing both a DMT-containing extract and monoamine oxidase inhibitor (MAOI)-containing extract from plants. The combination of DMT and a MAOI is built upon the chemical principle of ayahuasca, whereby the addition of a MAOI will prolong the trip. Changa can be smoked in a joint, pipe, bong or vaporized with a vape pen.
  3. Injected: DMT must be injected in its salt form (DMT fumarate).
  4. Ingested/Orally: Consumed orally in the form of ayahuasca.

Although DMT occurs naturally in plants, it can also be synthesised chemically, producing DMT in its base or salt form. The term ‘freebase DMT’ refers to DMT in its pure alkaloidal form and is insoluble in water, whilst ‘DMT fumarate’ refers to the salt form and is water soluble.

DMT is a psychedelic tryptamine. It is an indole alkaloid and has a chemical structure similar to the neurotransmitter serotonin. This similarity in structure between DMT and serotonin allows it to bind to serotonin receptors. Specifically DMT acts as an agonist of the 5-HT2A receptor, whereby it binds and stimulates a response. It is thought that 5-HT2A receptor agonism plays a major role in the hallucinogenic effects of DMT. The 5-HT2A receptor is associated with several other classical psychedelics, including psilocybin and LSD, and consequently these psychedelics can often be referred to as serotonergic psychedelics.

Psychological effects

DMT is rapidly acting and effects are typically observed around 2-5 minutes after consumption and last around 15-20 minutes. Despite its short-lived effects, DMT is known as one of the most powerful psychedelic drugs. The subjective effects of DMT can often be meaningful but will vary with dosage. These include:

  1. Eliciting intense visual alterations and hallucinations, specifically colourful and geometric forms
  2. Profound spiritual or mystical experiences
  3. Varying alternations in mood and emotion, including experiences of euphoria, calm, fear and anxiety
  4. Perceived encounters with external entities, which are often described as elf-like.
  5. Altered sense of time and place
  6. A sense of depersonalisation or out of body experiences
  7. Potential auditory hallucinations
  8. Evocation of powerful memories

Physiological effects

DMT is associated with low toxicity and is easily metabolised by the body. However, there are physiological implications and associated risks to be aware of. These include elevated blood pressure and increased heart rate, which is particularly risky for those with heart conditions. The impaired cognitive and motor function poses a personal safety risk and presents further reason for DMT to be consumed in a safe environment with a sober sitter. It should be noted that at high doses there are some reports of seizures, respiratory effects and comas.

DMT, when consumed in the form of ayahuasca, has a long history of traditional medicinal use for numerous indigenous tribes across the Lower and Upper Amazon. The therapeutic potential of ayahuasca as a therapy tool in psychotherapy has generated significant clinical interest and several clinical trials have reported beneficial effects in the treatment of addiction and depression.

The growing mainstream appreciation for the therapeutic potential of ayahuasca (DMT-containing brew) and other classical psychedelics has generated increased scientific interest as to whether DMT has therapeutic potential. Scientific studies have demonstrated similarities between DMT and psilocybin, whereby DMT is able to produce a comparable mystical experience to that of psilocybin. It is suggested that psilocybin alters brain activity and enables the brain to reset. Therefore, recent evidence that DMT causes changes in human brain activity could be of therapeutic value. These similarities suggest that DMT may have a similar therapeutic potential to psilocybin in treating psychiatric disorders such as depression and anxiety.

DMT is a powerful psychedelic drug and, as with any drug, it’s important that there is an appreciation for both the psychological and physiological risks associated with its use.

DMT induces a particularly potent psychedelic experience consisting of intense visual alterations and hallucinations, alongside alterations in emotion and mood. The intensity of the trip can be emotionally challenging for some people, inducing states of panic, anxiety and paranoia. For some people DMT produces an out-of-body experience or depersonalisation, which can be an overwhelming experience. Similar to all psychedelics, the psychological risks can be minimised by ‘set and setting’, ensuring that both your mind-set is stable and well prepared, and that the environment is safe and encouraging. A sober sitter is an important safety measure to mitigate psychological harm.

Read more on DMT harm reduction in the harm reduction advice section.

Similar to other psychedelics, history of mental health illness (such as schizophrenia, psychosis and bipolar disorder) may increase the likelihood of an unpleasant experience and there is the risk DMT may exacerbate these conditions. However, there is still a limited understanding of the risks associated with the use of psychedelics in those with pre-existing mental health conditions.

It’s important to understand that DMT affects the serotonin system and therefore should not be taken in consumption with other drugs that also alter the serotonin system. This can result in a potentially life-threatening condition called serotonin syndrome. This includes some antidepressants and selective serotonin reuptake inhibitors (SSRIs).

Prescription drugs with an associated risk:

  1. SSRIs
  2. Antipsychotics (although many will also block the actions of DMT)
  3. Opioids, especially tramadol
  4. Antihypertensives
  5. Central nervous system depressants
  6. Vasodilators

DMT should not be mixed with alcohol or other drugs and an understanding of the effects and mechanism can provide insight into the risks associated with mixing it with other drugs.

Key drug combinations to avoid are listed below:

  1. DMT shouldn’t be mixed with tramadol due to the increased risk of seizure
  2. DMT shouldn’t be mixed with other stimulants including cocaine and amphetamines
  3. DMT shouldn’t be mixed with cannabis
  4. DMT is a powerful psychedelic and mixing it with other hallucinogens carries the risk of making the trip more intense
  5. DMT shouldn’t be mixed with any recreationally used prescription drugs that are known to potentially interact with it. This includes all those listed above

DMT, along with other classical psychedelics, is not addictive. However, tolerance can develop with frequent use, whereby a higher dose is required to achieve the same effect.

DMT is a powerful psychedelic drug that can produce a rapid and intense hallucinogenic experience. Informed harm reduction advice can help to mitigate some of the associated risks.

Being educated and prepared

It is important that you fully educate yourself on the health risks and drug interactions associated with DMT. It is important to ensure that the correct form and method of consumption is used, as well as a suitable dose. The particularly intense nature of DMT makes it important that sufficient preparation is done. This includes an awareness of the psychological and physical effects that DMT may induce. Preparation is also linked to the person’s mind-set.

Set and setting

‘Set’ refers to a person’s mind-set including their mood, thoughts and expectations. This can have a significant effect on the experience of the trip and therefore it is advised that DMT is only consumed when a person is in a positive and stable state of mind. ‘Setting’ refers to the environment and social situation in which the drug is consumed. DMT should be consumed in a safe and calm environment, due to the intensity of the trip and the potential motor impairments.


The presence of a sober sitter is particularly recommended with DMT. The sitter can provide reassurance and support during and after the trip. The sobriety of the sitter is essential and can provide a sense of clarity and guidance through any disorientating or overwhelming experiences.

Does the human brain produce DMT?

There has been extensive debate as to whether DMT is produced in the human brain. A lot of the debate has been focused around the pineal gland, a tiny organ in the centre of the brain, which had been popularised by many as the primary producer of DMT. However, currently scientific evidence to support this theory remains very limited.

Trace amounts have been detected in human blood and urine, supporting the idea of the endogenous production of DMT in the human body. Although a recent study detected DMT in the pineal gland of rats, there has been no evidence of this in the pineal gland of the human brain. A subsequent study demonstrated that DMT is still produced in the rat brain after removal of the pineal gland, adding further fire to the debate as to whether the pineal gland is the primary source of DMT. Understanding endogenous DMT production in the human body and its potential roles in physiology remains an understudied area and extensive further studies are needed.

Are DMT and 5-MeO-DMT similar?

5-MeO-DMT stands for 5-Methoxy-N,N-Dimethyltryptamine. While they may look similar, and have similar chemical structures, they induce different experiences and should not be confused. For more information on 5-MeO-DMT click here.

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Ayahuasca is a psychedelic tea originating from the Upper Amazon in South America.  It is typically prepared from two plants– Psycotra viridis, containing the psychedelic compound DMT (N,N-Dimethyltryptamine), and Banisteriopis Caapi (the ayahuasca vine) which contains monoamine oxidase inhibitors (MAOIs) that prevent DMT from being broken down in the gut and liver. This combination allows DMT to have psychoactive effects when taken orally, and prolongs the intense psychedelic experience.

Ayahuasca has a long history of ceremonial consumption among various indigenous populations throughout the region, in countries such as Bolivia, Ecuador, and Peru. Ayahuasca is considered in its traditional context as an important element of shamanic tradition and as a medicine. As such, it is consumed within a ceremony or ritual under the guidance of a Shaman; a person of significant social standing who is sought for the healing of physical, emotional and psychological issues.  More recently, its psychedelic properties and therapeutic potential have attracted significant attention in the global West, with a rapidly-emerging tourism sector centred around offering the ayahuasca ceremony to international visitors at ayahuasca retreats.

As a psychedelic drug, ayahuasca is increasingly consumed outside of traditional retreats and ceremonies due to the online availability of the plants used in ayahuasca preparation. New trends in consumption have led to controversy around the impact on the traditional communities where its plant components grow, and the potential risks of unsupervised use. For a deeper exploration of these debates, please find here the Drug Science podcast episode with Dr Simon Ruffell on ayahuasca.

Ayahuasca is a reddish-brown tea. Traditionally, ayahuasca contains the Banisteriopis Caapi vine and psycotra viridis as its base. However, there may be regional variations in the preparation and it is common for other plants to be included in the admixture. Some additions may have psychoactive properties of their own, and these may also be potentiated by the β-carbolines of the MAOI. Substitutions are also possible; plants such as Mimosa, Acacia, Syrian Rue containing the same active compounds sometimes replace their original counterparts.

DMT is an indole alkaloid, acting as an agonist upon the 5-HT2A receptors (along with all other classic psychedelics such as LSD, psilocybin, 5-meo-dmt, etc). It is capable of producing strong visionary effects and other indicators of altered state of consciousness. Under normal circumstances, DMT is inactive when consumed orally, as it is denatured by an enzyme found in the stomach before it can take effect.  Therefore, it is more commonly vaporised, or, as has been the case in some clinical trials, administered intravenously. In ayahuasca preparations however, the addition of a MAOI (β-carboline compounds such as harmine, and harmaline) slows this process of enzyme oxidation, allowing oral preparations to produce a profound psychedelic experience, sometimes referred to as an ‘ayahuasca trip’.

To find out how DMT works in the brain, click here.

As with other 5-HT2A agonists (such as LSD, psilocybin, 5-meo-dmt etc), a serotonergic response is observed. The subjective effects – which last approximately four hours – are highly variable and often difficult to describe, but can include:

  1. Intense closed and open eye visuals
  2. Re-experiencing of memorable events
  3. Distortions in sense of time, place, and sometimes sense of self
  4. Possible auditory and sensory hallucinations
  5. A deep state of introspection
  6. Profound spiritual experiences
  7. Perceived contact and interaction with other entities
  8. Temporary alterations in mood and emotion that can range from terror to euphoria.

‘Autobiographical’ elements of content are often reported by those experiencing ayahuasca-induced visuals. The resurgence of memories, and a ‘third person’ perspective on life events have frequently been reported.

The psychedelic effects may be preceded by nausea, vomiting, and sometimes diarrhoea. This emetic action is perceived of as a cathartic expulsion in traditional settings, and is welcomed as part of the overall experience.

Emerging research into ayahuasca on brain function and potential clinical applications attest to some positive effects on mental wellbeing.

In clinical settings, preliminary observations indicate anxiolytic and antidepressant effects, along with reductions in suicidality in people with treatment-resistant depression. It may have a role in supporting people through addiction rehabilitation; clinical trials have demonstrated improvements in hopefulness, empowerment, mindfulness, and quality of life and outlook have been observed in those with dependency on other substances, as well as reductions in self-reported use of tobacco, alcohol and cocaine.

The therapeutic potential of ayahuasca has been reported after use in religious and ritual practices. It is consumed as a religious sacrament in a number of Brazilian syncretic churches. Studies have consistently reported higher wellbeing scores in churchgoers who are regular ayahuasca consumers (usually twice per month), when compared with members of non-ayahuasca churches.

Ayahuasca has a long history of use, with very few reported incidents of harm. Clinical studies (both animal and human) indicate it to be extremely safe when appropriate dosage, setting and supervision is applied. There is very little risk of toxicity, as is the case with most of the classical psychedelic drugs. The most frequently reported adverse event is an intense, challenging experience that can be emotionally difficult. For some, prior traumas can be revisited, and sometimes painful emotions require processing. Usually, this is temporarily unpleasant and causes no lasting harm.

As with all substances, there is risk around the composition of the preparation. Toxicological studies of ayahuasca ‘brews’ have revealed that concentrations of both DMT and the β-carboline MAOIs vary substantially across preparations. Many different types of additional plant matter  have been reported, some of which may pose risk of interaction or potentiation. Storage duration and transport conditions have also been shown to affect composition, with significant changes observed to the harmala alkaloids (present in the MAOI).

Caution is also advised in any setting where usual decision-making and awareness may be compromised. The risk of sexual assault and accidental injury or death is higher where psychoactive substances are used.

Although ayahuasca is pharmacologically safe at usual doses, there are some pre-existing conditions and medications that may preclude the use of ayahuasca. Common prescription drugs with interaction risks include:

  1. Other MAOIs (sometimes prescribed as antidepressants)
  2. Antipsychotics
  3. Antihypertensives
  4. Selective Serotonin reuptake inhibitors (SSRIs)

SSRIs, commonly prescribed for depression, present a hypothetical risk of Serotonin Syndrome when combined with MAOIs. Some medications may also limit the efficacy of ayahuasca, especially if they bind on the same receptors. Prescribed medications should not be suspended without consulting your doctor first.

Diagnoses of some types of mental illness (such as schizophrenia, history of psychosis, and bipolar disorder) are considered an exclusionary criteria in many settings.

Typically, full or partial fasting or is recommended prior to an ayahuasca experience. This not only reduces the chances of vomiting, it also promotes maximum absorption of the ayahuasca, and prevents potentially dangerous drug-food interactions. For example it is believed that foods high in tyramine (such as many cheeses and meats) may interact with β-carboline alkaloids present in ayahuasca.

Ayahuasca should not be consumed together with alcohol or other drugs. In particular, amphetamines should be avoided, due to their hypertensive action which when combined with a MAOI could prove fatal. Although, this particular drug interaction does not appear to be documented with ayahuasca. Detailed information on drug interactions can be found here.

Ayahuasca is commonly used in traditional settings with other ethnobotanical or otherwise naturally derived psychoactive substances. These include:

  1. Tobacco (rapé; mapacho)
  2. Kambo (from the Kambo frog)
  3. 5-MeO-DMT (from the Bufo Alvarus toad)
  4. Peyote (mescaline cactus)
  5. Psilocybin (from certain types of mushroom)
  6. Yopo (N,N-DMT, 5-MeO-DMT and Bufotenine containing seeds).

Caution should be exercised even if these options are presented as a usual part of the programme. Although there is little anecdotal evidence of adverse effect, few studies have looked at the clinical implications of taking these substances in close proximity.

Ayahuasca, like the other classical psychedelic drugs, is not addictive. Despite the documented (and further anecdotal) benefits, the trip process can be unpleasant and difficult, and therefore does not lend itself to regular use. Psychedelics in general also demonstrate a pharmacological mechanism of short-term reduced efficacy (tolerance) which inhibits their prolonged or frequent use. In fact, ayahuasca is valued for its anti-addictive properties and its potential role in supporting those with dependency on other substances is being explored.

If you have already made the decision to consume ayahuasca there are a number of precautions you can take to reduce the risk of harm. Adequate supervision is strongly advised; a person who is both sober and experienced with the psychedelic state can support any challenging aspects of the trip experience. If this is in a retreat setting attention should be paid to screening processes, preparation, supervision arrangements and integration, as well as the independent reviews by previous participants where available. The setting should be as comfortable and secure as possible and free of interruptions. As mentioned, any pre-existing conditions or medications should be discussed with a physician wherever possible.

Ayahuasca is hailed by some proponents as an all-round panacea for physical and mental health. While there are many interesting research avenues being/to be explored, it is dangerous to assume that any one substance can ‘cure’ ailments for which we do not (yet) have an evidence base for. This particularly applies to any choices one may make about rejecting or discontinuing mainstream medical accompaniment. Prescription medication should not be suspended to take part in, or as a result of, an ayahuasca experience without medical guidance.

It would be a harmful misconception for ayahuasca to be viewed as a recreational drug, or for ceremonies and other organised settings to be viewed as ‘drug-fuelled’ gatherings. On the contrary, the taking of ayahuasca is often referred to as trabajo (‘work’) in traditional contexts; from the nausea and vomiting, to the solitary introspection and the potentially challenging emotional experiences, it is not considered an easy or reliably pleasant activity. It is not therefore used as a recreational substance and is rarely taken at parties, festivals and nightclubs.

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5-MeO-DMT Molecule and Chemical Structure

5-MeO-DMT is a natural psychedelic drug found in the venom of the Colorado River toad, Bufo Alvarius, also known as the Sonoran Desert toad. Smoking 5-MeO-DMT induces a short but intense psychedelic experience or ‘trip’, with hallucinogenic effects that are significantly stronger than those induced by DMT (the primary psychoactive molecule found in Ayahuasca). Despite this, the difference between 5-MeO-DMT and DMT is just a single Methoxy group, and it is structurally similar to other psychedelic drugs such as psilocybin and DMT.

Also present in at least nine families of plants, trees, and shrubs, use of 5-MeO-DMT as a psychedelic drug has been traced back some 3000 years in the form of crushed seeds known as ‘Yopo’, which are still used in spiritual ceremonies in Venezuela, Columbia, and Brazil. 5-MeO-DMT was first synthesised in 1936 by chemists Toshio Hoshino and Kenya Shimodaira and identified as an active component of Amazonian snuffs in 1959. Since then, 5-MeO-DMT has been detected in human blood, urine and cerebrospinal fluid.

Legal 5-MeO-DMT was readily available online as a ‘research chemical’, and grew increasingly popular before being made illegal in the USA in 2011, after which many other countries followed suit and banned the substance.

Due to these restrictions, research into 5-MeO-DMT is extremely limited and only a handful of studies have been conducted to date.

Bufo Alvarius Toad (Colorado River Toad)

As a defence mechanism, the Colorado River Toad secretes a white milky substance called ‘Bufotoxin’ from areas behind its eyes called ‘parotoid glands’. When dried this contains up to 30% 5-MeO-DMT by mass, alongside other substances such as Bufotenine, DMT, NMT, DET, N-Methylserotonin and Bufogenin. There is no evidence of a difference between synthetic 5-MeO-DMT and that secreted by the Bufo Alvarius toad, meanwhile there are concerns regarding the environmental impact that Bufotoxin collection may be having on local toad populations at the United States and Mexico border.

The 5-MeO-DMT content of natural toad secretions can vary greatly between samples, which makes accurate dosing more difficult. This can be dangerous because 5-MeO-DMT is very powerful, even at low dosages, and the effects are highly dose-dependant, following a steep dose-response curve.

Synthesised 5-MeO-DMT

5-MeO-DMT is most commonly consumed in the form of a synthetic white, crystalline powder. Typical doses of 5-MeO-DMT are very small, typically 5mg, so care should always be taken by using accurate scales and researching the appropriate doses. 5-MeO-DMT in this form is typically either vapourised in a pipe and inhaled or less commonly insufflated (snorted).

Anadenanthera seeds (Yopo)

Some trees under the genus Anadenanthera contain 5-MeO-DMT. There is a long history of use of these seeds as shamanic snuffs in South America. Once the seeds have been toasted they are ground, sometimes mixed with other materials such as Ash and Tobacco, and forcefully blown up the nose of a user via a tube.


Ayahuasca is a traditional tea, originating from South America. It is made from a mixture of psychedelic plants and a vine containing a mono-amine oxidase inhibitor. The MAOI prevents gut enzymes from breaking down the psychedelic components of the leaves, making them orally active. Some Ayahuasca recipes include 5-MeO-DMT containing plants, however, this combination has been shown to be fatal, and there is evidence to show that mixing 5-MeO-DMT with MAOIs can be potentially dangerous.

For more information about Ayahuasca, see our Ayahuasca Drug information page.

After being vaporised and inhaled 5-MeO-DMT quickly passes the blood-brain barrier. It shares a similar chemical structure with the neurotransmitter serotonin, which means it can fit into some of the serotonin receptors in the brain where it acts as an agonist, meaning it stimulates the receptor – especially the 5-HT2A subtype of the serotonin receptor.

Stimulation of these Serotonin receptors leads to the psychedelic state e.g hallucinations, and can affect mood and body temperature.

5-MeO-DMT is a relatively short-acting psychedelic drug and the ‘trip’ usually lasts less than 30 minutes when smoked, and up to 45 minutes when insufflated. When vapourised and inhaled the effects begin almost instantaneously, which means it is very important to be in a safe and comfortable environment to avoid accidents

Users often report overwhelmingly intense experiences which can sometimes be difficult to remember. Accounts of mystical union, feelings of non-duality and experiences of a transpersonal nature are not uncommon. Often uncomfortable bodily sensations such as a rapid heart rate, nausea and pressure in the chest can be present.

The alterations to perception as a result of taking 5-MeO-DMT often include auditory and visual hallucinations, internal scenes, time perception distortions and cognitive and/or emotional shifts. Some users report that 5-MeO-DMT is less visually intense than NN-DMT.

Similar to other psychedelic drugs like psilocybin and LSD, experiences can range from being euphoric and spiritually significant to dysphoric and psychologically scarring.

There is research which suggests that 5-MeO-DMT could have associations with improvements in anxiety and depression. It is sometimes used as an adjunct to Ibogaine therapy for the treatment of addiction. This may be effective because 5-MeO-DMT has been shown to down-regulate a receptor involved in the reward mechanism of drug abuse. The same study found that cells treated with 5-MeO-DMT show a similar response to anti-depressant medications. Further research is needed to investigate 5-MeO-DMT’s potential anti-depressive properties.

There have been suggestions that 5-MeO-DMT could be of use in understanding the neurobiological basis of hallucinations and for antipsychotic drug development.

Sleep disturbances, persistent anxiety and panic attacks have been reported in some individuals after a single experience with 5-MeO-DMT.

Unwanted or overwhelming realisations or insights can be hard for some people to integrate after their experiences. Some accounts describe persistent psychological disturbances and resurfacing of the effects lasting for weeks after use. Using a low, precisely measured dose can help to avoid unexpected or overly powerful effects.

As 5-MeO-DMT is most commonly smoked, anyone with a lung condition or asthma would be at a higher risk of adverse effects. Additionally, as 5-MeO-DMT can increase heart rate, people with cardiac problems should avoid using it.

People predisposed to or suffering from schizophrenia or psychosis might experience an onset or worsening of symptoms from 5-MeO-DMT use.

There is evidence to show that mixing 5-MeO-DMT with MAOI drugs can be dangerous and increase the risk of harm. There have been deaths from this combination.

There is also an increased risk of cardiac complications if combined with stimulants.

Alcohol should also be avoided to reduce the risk of vomiting and aspiration.

A study of 5-MeO-DMT users concluded that it is generally ‘used infrequently, predominantly for spiritual exploration’ and ‘has low potential for addiction’.

82% of the sample reported using 5-MeO-DMT for spiritual or healing/psychological purposes, indicating that it is not a substance which is commonly used recreationally.

Additionally, the majority of the sample indicated that they used it less than once a year, with the majority of use taking place in ceremonial or supportive contexts. Therefore, compulsive re-dosing and addictive behaviour patterns are unlikely to be seen with 5-MeO-DMT.

5-MeO-DMT in moderate to high doses will often leave the user incapacitated, so it is important to have someone present to prevent an individual from injuring themselves if they start moving around. Because of this, it is also advisable to be aware of the environment in which it is consumed, avoiding obvious hazards such as bodies of water and steep drops.

Occasionally, effects can vary from abnormal vocalisations and unusual body movements to complete unresponsiveness. Therefore, the person accompanying a 5-MeO-DMT user should know how to place someone in the recovery position, as vomiting is sometimes reported. Bear in mind that unconsciousness, along with breathing difficulties, is a sign of overdose and should be monitored.

Although 5-MeO-DMT is sometimes used in South American Ayahuasca recipes, it is generally considered dangerous to mix with any MAOI.

As 5-MeO-DMT is active in doses from as small as 3mg, weighing the dose carefully with a precise scale is important to avoid accidental overdose.

There is the potential for 5-MeO-DMT to be confused with N,N-DMT, a mistake which can be potentially problematic due to 5-MeO-DMT being 4-10x more potent than N,N-DMT and having a lower toxicity threshold. For more information on N,N-DMT, see our DMT Drug Information page. Home testing kits are available to buy online which can distinguish between the two. Always start with low doses to be safe.

There is a popular myth regarding ‘licking’ toads to get high. This is dangerous with Bufo Toads as Bufotoxin contains ‘digoxin-like cardiac glycosides’ which can be fatal. There have been reports of poisonings and even deaths from the ingestion of Bufo Toad toxins by humans.

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Kratom (Mitrogyna Speciosa) is a tree indigenous to South East Asia, with leaves containing the psychoactive alkaloids mitragynine and 7-Hydroxymitrogynine. It has a long tradition of use by farmers and other manual workers in its native region, who claim it increases productivity. In recent years, the leaves of this plant (usually prepared as a tea) have been gaining popularity internationally, especially in the US. Whilst not under international control (as is often the case with ethnobotanical psychoactives) its legality varies between regions and countries. Little is known about extent of use in Europe, particularly in countries where it is illegal such as the UK, having been controlled under the Psychoactive Substances Act since 2016.

There several types of Kratom, characterised by different colour ‘veins’ in the leaves and sometimes different growing regions, which are said to have impact the plant’s primary indications. Differences in preference for particular types of kratom are not yet well understood. Laboratory analysis has so far detected no significant difference in the major alkaloids in the resulting plant matter, and the plants which produce the different colour veins are not separate ‘strains’ of kratom in the true botanical sense. It is possible that asides from these two well-known alkaloids, there are other compounds within the plant which also produce an effect, either alone or in combination, which may account for these subjective differences.

Kratom is consumed orally. It is usually sold as a dried greenish powder, which can be swallowed neat, chewed, or prepared as a tea or cold beverage. Less frequently, it is sold in capsule or concentrated extract form.

Kratom contains over 40 different alkaloids, plus a number of other compounds. The two which attract the most attention are mitragynine and 7-hydroxymitragynine; alkaloids which act as partial agonists on the opioid receptors, meaning they produce somewhat similar, but milder, effects to opioid-based medications. This is partly due to the low concentrations of psychoactive compounds within the plant matter (usually 1 – 1.5%) meaning relatively large amounts of kratom needs to be consumed before a noticeable psychoactive effect occurs. Bodily effects maybe noticeable at slightly lower doses; some users report the principle (or only) effect as being an absence of fatigue or pain. Interestingly, mitragynine also has a broad affinity with many other receptors in the body, potentially explaining its complex effect on energy and mood.

There is evidence that in smaller quantities, kratom can produce a mild stimulatory effect, hence its traditional use as a aid with hard, physical labour. These stimulatory effects are not generally considered intense enough to attract the interest of those who use ‘party’ or ‘club’ drugs such as amphetamines. In larger doses, it may have an analgesic quality, and also possess sedating and muscle-relaxing effects.

Kratom is not widely used for recreational purposes – it is more commonly used for self-medication. Emerging data suggests that outside of its traditional context, kratom is more frequently used in an attempt to address chronic pain, sleeplessness, and/or to support opioid addiction withdrawal and recovery. More research is needed to scientifically assess its potential therapeutic applications, but the anecdotal evidence for these effects is strong.

Kratom is less likely to cause harm to health than many other illicit drugs and prescription medications, particularly those from the opioid family, of which it mimics some effects.

None the less, there some side-effects of kratom. Similar to opioids, it can produce agitation, tachycardia, constipation, vomiting and nausea. It does not, however, appear produce the respiratory depression which is characteristic of opioid overdoses. There have been a small number (this varies according to the source consulted) of fatalities internationally where kratom was implicated. This was usually because kratom was detected on post-mortem toxicology. However, in almost all cases, a number of different drugs were detected, which may contributed to, or been responsible for, the death. According to the US Center for Disease Control (CDC)  ‘Postmortem toxicology testing detected multiple substances for almost all decedents…Fentanyl and fentanyl analogs were the most frequently identified co-occurring substances.’ It also needs to be considered that as the vast majority of regular kratom users report experiencing chronic pain, or are in recovery from addiction to another substance, they are already at increased risk of death in any given year. Interestingly, no deaths attributed to kratom have been reported in Asia.

People who have impaired liver function, or who are taking prescription medications which may be changed by the liver, may be more at risk of harm, as kratom is believed to temporarily slow down functioning of this organ.

Taking more than one psychoactive drug at a time is always riskier than taking a single substance. Consuming Kratom alongside other opioids (whether illicit drugs or prescribed medications) may be very dangerous, as this likely to potentiate the effects, and the risks of each substance increase. Using alcohol will also raise the likelihood of experiencing negative effects. Little is known about this combination, but in general, central nervous system depressants such as alcohol pose even more risk when combined with either stimulants or sedatives.

There is some evidence that kratom may cause dependence, if taken in sufficient quantities for an extended period of time. Some people report difficulty in stopping or reducing daily use. Withdrawal symptoms are likely to be much milder than those associated with opioids, bearing in mind one of the most common uses of Kratom is to lessen the effects of opioid withdrawal in those with existing issues with addiction. As previously mentioned, the most common mode of use is oral ingestion, which does not lend itself as easily as to addiction, as the onset of effect is longer and milder due to the metabolisation process which accompanies this.

Kratom is a comparatively low-risk substance when taken in small doses. Those who have decided to use kratom are advised to begin with small amounts, as individual tolerance levels will vary. Taking too much kratom can be unpleasant; nausea vomiting and dizziness are common side effects in such instances. Concentrated preparations, such as liquids, are best avoided – accurate dosing is difficult as the strength is often unknown There may be other ingredients present which pose risks of their own – as with any drug purchased in a non-regulated market, there is always the possibility of adulteration. As noted above, kratom can produce mild withdrawal symptoms after regular use, so caution is advised with regards to frequency of consumption.

The US Food and Drug Administration declared kratom to contain ‘opioid agonists’ in 2018, and The CDC states that Kratom is not an opioid. Nonetheless, its action on the Mu-opioid receptors means kratom is sometimes erroneously ‘lumped together’ with opioids such as morphine and heroin. It does not display the same properties, and does not pose the same level of risk of abuse, or in terms of respiratory depression (Opioids such as heroin, suboxone etc can slow breathing down to such an extent that it can cause death – a 2019 review concluded this was not the case with kratom).

In 2016, the Drug Enforcement Administration expressed intent to place both mitragynine and 7-hydroxymitragynine into schedule 1, which would have made possession or sale of kratom illegal across the US. Protesters organised a march and a petition, which garnered over 120,000 signatures to oppose the ban. Of the 23,116 comments which were submitted during the public consultation, 99.1% supported kratom, and included positive accounts from a large number of law enforcement officials, heath care professionals and scientists, who overwhelmingly stressed its potential role in addressing the opioid epidemic currently facing the US.

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“Synthetic cannabis” is a common, but misleading, term that refers to a class of substances more accurately called cannabinoid receptor agonists or synthetic cannabinoids. Whereas cannabis usually refers to the dried flowered buds of the actual plant, which derives its main psychoactive effect through THC, synthetic cannabinoids get their name from their action on various cannabinoid receptors in the brain.

Sacrificing accuracy for simplicity, people in public office, the media, and law enforcement use the term “synthetic cannabis” or the brand names of products sold, such as “Spice” or “K2,” that are known to contain various synthetic cannabinoids. “Spice” is now widely used to mean any and all synthetic cannabinoids, rather than any individual compound.

Many of these substances have different chemical structures than THC, the main psychoactive ingredient in cannabis, and bind very much stronger (10-80 fold) than THC to receptors in the brain. This means that they can produce very different effects than THC and is one possible reason for the higher rates of some of the more extreme side effects that are only occasionally seen in adverse reactions to cannabis.

The emergence of synthetic cannabinoids has mirrored the same trends seen with other new psychoactive substances. Due to the ongoing prohibition of cannabis, emergence of the synthetic cannabinoid market over the last decade has met demand by being a legal or quasi legal alternative. Consequently – users could avoid possession charges and pass drug tests, particularly in prisons/on parole and in the workplace. Secondly, new psychoactive substances, as they were legal, were considerably cheaper than their illicit alternatives.

As people found many of the side effects strong and unpleasant, the use of synthetic cannabinoids decreased in the general population. Two key populations remain – prisoners and the homeless. As mentioned, synthetic cannabinoids are a) highly potent and b) hard to detect. Accordingly, they are ideal for smuggling into prisons, where supply is scarce. The high potency also accounts for the high incidence of use in the homeless – they produce a profoundly dissociating and depersonalising experience which helps insulate the user from the cold, harsh, and unpleasant environment of being on the streets.

Cannabis is a natural plant that grows both in the wild and is cultivated for its medicinal properties and for recreational use. Though synthetic cannabinoids are considered chemical relatives or analogues to substances in cannabis, they are not actually found in plant-based cannabis and therefore have chemical and pharmacological properties largely unknown outside of the laboratory.

Synthetic cannabinoids are mistakenly considered to closely mimic the effects of cannabis, but in fact there are significant differences. As their name suggests, synthetic cannabinoids, like THC and other substances in cannabis, affect the brain by stimulating activity at various cannabinoid receptors.

Although research is limited, preliminary studies suggest that positive effects include:

  1. Feeling stimulated and energetic;
  2. Increased appetite;
  3. Producing a dream-like state,

Negative effects include:

  1. Overdose and temporary psychotic states and unpredictable behaviours;
  2. Sudden increase in body temperature, heart rate, coma and risk to internal organs (PMA);
  3. Hallucination and vomiting;
  4. Confusion leading to aggression and violence;
  5. Seizures
  6. Respiratory failure
  7. Intense comedown that can cause users to feel suicidal.

The severe side effects are likely due to two key reasons:

  1. Very high potency & strong binding to receptors in the brain;
  2. An absence of naturally occurring cannabinoids found in herbal cannabis (like cannabidiol/CBD) which normally counteract the effects of THC.

These substances are generally much more harmful than plant-based cannabis. Many of the adverse reactions to synthetic cannabinoids have been reported to involve dangerous, lethal physical symptoms. These include seizures, aggression and agitation, as well as respiratory failure and loss of consciousness. Adverse reactions to natural cannabis typically involve symptoms resembling anxiety and panic, which though worrisome, are not lethal.

Yes. Synthetic cannabinoids are pro-psychotic, and individuals with a history or family history of psychosis and mental health conditions are at elevated risk. They are also pro-convolsant, and individuals with a history or family history of epilepsy and other seizure disorders are at elevated risk.

Very little is known. A 2013 survey by the Scottish Drug Foundation found:

  1. Increase in mental health issues including psychosis, paranoia, anxiety, ‘psychiatric complications’;
  2. Depression;
  3. Physical and psychological dependency happening quite rapidly after a relatively short intense period of use (weeks).

A synthetic cannabinoid is cannabis made in a laboratory

Synthetic cannabinoids and the active psychoactive ingredient in cannabis, THC, are very different drugs. They bring about serious, life threatening side effects and are only linked to cannabis in that they bind to the same receptor in the brain as THC.

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Salvia divinorum, a relative of the herb sage, grows wild in parts of Mexico but is also cultivated around the world. The plant’s leaves have traditionally been used by Mazatec shamans for medicinal purposes and healing rituals. The chemical thought to be responsible for the psychoactive effects is salvinorin A. To the surprise of scientists, this molecule has no nitrogen atoms, which is very peculiar for a drug with powerful psychoactive effects.


Fresh leaves can be chewed. A salvia ‘quid’ (lump of leaves) is crushed slowly with the teeth and held in the mouth for about half an hour. Dried leaves are soaked in water first before chewing. The salvinorin A is absorbed through the lining of the mouth, so chewing fast and swallowing is ineffective. Some brush the inside of their mouth with mouthwash, or eat chillies before chewing, in order to increase blood flow and so boost the absorption of the chemical. Just 10 strong leaves have given some people realistic visions of being in another place, so users should be cautious with quantity, and start with a small amount the first time. With this precaution, chewing is likely to be the lowest risk way of using salvia. The effects take about 15 minutes to kick in and last an hour or so before fading, peaking in about 30 minutes.

A variety of tinctures made to be taken by mouth have also been observed, these are concentrated and require even more care to prevent a stronger-than-desired experience.


Some people smoke dried salvia leaves in order to get a stronger experience of the drug. Using a water-pipe (bong) and a cigarette lighter is a popular method. Using matches is risky, as you are likely to drop it as soon as the drug kicks in. The problem with smoking dried salvia leaf is that you need to inhale a great deal of thick smoke over 2 or 3 minutes to get an effective dose as the leaves naturally contain so little of the drug. This is unpleasant, probably unhealthy, and difficult to achieve for most people.

However, salvia for smoking is now mostly purchased in the form of dried, ground-up salvia leaf which frequently has had a concentrated salvia extract added. This allows the entire dose of Salvinorin A to be consumed in just a few puffs or even just one inhalation. This gives a large risk of having an unpleasantly overwhelming experience. Extreme caution must be taken with these products. If you intend to use them, start small and work your way up, rather than jumping in at the deep end.

Concentrated salvia leaf looks a bit like dark dried herbs. This product is usually described by how many times the potency of the original dried salvia leaf has been fortified (e.g. 5x extract, 20x, or even 60x). Quality control for products like these is virtually non-existent. This means that if you buy salvia you cannot rely on the claimed strength of the extract being trustworthy and there is the possibility that salvinorin A may be replaced by another substance. Experience reports on websites like suggest that people have gone through very powerful experiences from products labelled as being any of the available strengths.

Salvia is a very unusual dissociative hallucinogen which does not have the same action in the brain as LSD and other classical psychedelics, or dissociative drugs like ketamine.  Its effects are probably due to its action on the κ-opioid receptor, but how this produces the experience of salvia is unknown.

Salvia is not a drug that reliably makes users feel ‘good’. People often take it out of curiosity and interest in exploring weird mental states, rather than for pleasure or fun. A few use it for personal spiritual reasons but it appears that most users do not tend to repeat these powerful experiences very often.

Salvia combines hallucinogenic and dissociative effects. At higher doses it can scramble current perceptions, memory and imagination so you can lose all sense of who and where you are and what is going on. Alternatively, you might find the trip meaningful, for example revisiting places from your past, which may appear to be as clear and real as normal experience. This means that, unlike most hallucinogens, when a salvia trip is intense, it is quite possible to be unable to determine what is real and what is not, and even forget you have taken a drug, which cause intensely disturbing ‘derealisation’ and fragmentation of identity.

When smoked, the effects of salvia come on in seconds, peak in the first 5 or 10 minutes and then decrease over the next half hour. The experience can be very unusual and for a minority of people taking salvia feels enlightening and has elements of beauty. However many find that it very difficult to make any sense of. Most people do not regret trying salvia, but plenty find it unpleasant and sometimes terrifying. Small doses of Salvia, for example when the plant is chewed, or smoked in an ineffective way, may make you feel odd and giggly.

If a large dose is taken, which can be with just one lungful of smoke, the user will have a very intense experience, in which no aspect of normal conscious reality stays the same, and it is common to forget that you have taken a drug, or even who or what you are. Every person will experience something different on salvia, and no two trips will be alike. Salvia can make your perception of time and the place you are in different. People can find themselves laughing hysterically. It can bring about cartoonish hallucinations, and even a total immersion in a dream reality outside of the normal universe. You can even experience encounters with other beings. Your whole body feels involved in a salvia trip, and sensations of falling, being pulled around, or floating are common. Some salvia effects are perhaps most comparable to other controlled psychedelic hallucinogens like LSD and DMT, although salvia works very differently in the brain. Salvia is more often scary and confusing, with the experience imposing itself on you whilst you have little control. The classic psychedelics more frequently give trips which feel meaningful and uplifting, where you often feel involved with the experience rather than the experience just happening to you, although salvia has the safety advantage of being very short-acting.

Salvia currently has no known medical use, however drugs that affect the κ-opioid receptor are thought to be worthwhile starting points for investigations for treatments against drug addictions.

There is no evidence that salvia is toxic to the body or brain but there has not been detailed scientific investigation on the potential of salvia to be harmful. Some people feel headachy or foggy-minded for a while afterwards.

In some countries, salvia is controlled, so make sure you investigate this first.

Traumatic experiences (bad trips and lasting symptoms)

Not enjoying salvia is common, but a truly traumatic experience seems very rare. The chance of it happening to you can probably never be ruled out, but is much more likely on very high doses, especially if you have never taken salvia before and if you are unprepared for its potentially powerful effects. If you are feeling negative emotions like anxiety, self-doubt or depression before you take the drug, bad feelings may become amplified.

People have believed they were dead or dying, that the walls were closing in, or that they were going permanently mad. Salvia often causes sensations of ‘depersonalisation’ and ‘derealisation’, where users lose track of their identity and question reality. For some, this is a profound and valuable experience, but for some it causes extreme fear and distress.

Although the salvia experience does not last long, some people report it feeling like it lasts for hours, or even forgetting that another sort of existence exists outside of the bad trip. During the trip, people can have panic attacks, become agitated, and try to escape. This risks injury to themselves and anyone who tries to restrain them.

There have also been cases, not formally reported in medical journals, of people who have found that a single salvia experience left them with derealisation (the feeling that nothing is real or can be relied upon) that lasted many days or more. They felt spaced out, miserable, and disconnected from reality. Others claim to have suffered lasting alterations of perception that echo the hallucinations during their trip (HPPD). It is important to repeat that these effects have not been scientifically documented, but they are serious enough to be aware of. There may be millions of people who have taken salvia without harm, and very few have suffered these serious lasting problems.


When you are tripping on salvia, you may be totally unaware of your real surroundings, but will often want to move around, which makes you vulnerable to dangerous accidents. Dangerous objects (car keys, knives) should be made inaccessible. Someone tripping strongly is less likely to suffer harm if they have constant supervision by a ‘trip sitter’. Unless it is unavoidable, the sitter should not try to physically restrain someone who is tripping so much that they are unaware of their surroundings, as the user may become frightened and lash out violently. If an appropriate setting is chosen, restraint should not be needed.

If you have had problems with your mental health, such as bipolar disorder or any psychotic illness, salvia could perhaps provoke bad reactions. In one almost unique case where a man developed a lasting psychotic illness after smoking salvia, it was thought that he may have been predisposed to schizophrenia, and the salvia brought on the appearance of symptoms.

Salvia does not appear to be addictive.

Salvia is legally available in many European countries, but this should not be taken as a reflection of its power. It can be distressing and even harmful, especially when used by people who are not prepared. There will always be a risk that you will have a horrible experience with salvia, but thoughtful preparation can help reduce the risks.

Chewing or smoking salvia

Considering what type of experience you want is important, For many people chewing leaves will give a sufficient experience with less of the risk of going too far than smoking might give. Even if you think you want a powerful experience, working your way up through lower doses will reduce the chance of getting more intensity than you wished for. This is true of most drugs.

Having a sitter

A sober and trusted friend, a ‘trip sitter’, can help look out for you, prevent accidents and may be able to reassure you if you are having an unpleasant or frightening experience. Getting comfortable in a safe place such on a carpet, with cushions around and dangerous objects removed, reduces the risk of injury.

Is salvia like cannabis?

No. Salvia is sometimes described as or compared with cannabis in the media, for example being referred to as a legal cannabis alternative because it is a smokeable herb and often not controlled. Most users do not find the drugs similar and they do very different things to the brain.

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chemical structure of psilocybin molecule, the psychedelic compound in magic mushrooms (shrooms)

Psilocybin mushrooms are naturally occurring mushrooms which contain the psychoactive compound psilocybin. More than 180 psilocybin-containing mushrooms species are found all over the world and can induce hallucinogenic/psychedelic effects when consumed. Psilocybin is converted by the body to psilocin, and this is the actual compound which produces their psychoactive effects. Additional chemicals commonly present in minor amounts include baeocystin and norbaeocystin, although the extent to which these contribute to the overall effects is unclear.

The small and potent liberty cap mushroom (Psilocybe semilanceata) is probably the most common and widespread species found in Europe. Other species occur in the wild, and Psilocybe cubensis is cultivated indoors.

Even though the psychoactive effects of every type of ‘magic mushroom’ are brought about by psilocybin, different types of psilocybin mushroom can have different types of psychedelic effects, and science is still researching how these effects can vary in type and strength over different strains.


Psilocybin mushrooms are naturally occurring — they either grow out of the ground or are cultivated from mycelium spores. Different strains of psilocybin mushrooms grow naturally all over the world and some people have been known to forage for them. Picking these mushrooms yourself, however, can be dangerous. There are over 10,000 species of known mushroom, some of which are poisonous to humans. Without knowledge of the different types, species and dangers of various fungi, it can be easy to confuse one mushroom with another and pick one which will leave you comatosed, as opposed to one which will give you a psychedelic trip.


Mushrooms are composed of around 90% water and so when dried they lose around 90% of their mass. This means that the same dose of magic mushrooms in a dried form will be around 10x lower in weight than a fresh dose.

If the moisture isn’t extracted from mushrooms when they’re picked they can rot fairly quickly, which destroys not only the mushroom itself but also the psilocybin contained within. Eating rotten magic mushrooms is never a good idea — the mould will cause severe stomach issues without any kind of psychedelic experience.

The market for magic mushrooms is illicit and unregulated as psilocybin mushrooms are illegal in almost every country. The danger of purchasing any kind of magic mushrooms (fresh or dried) is that, unless you’re an expert, you will not know exactly which strain you’re purchasing. There are many different types of psilocybe mushrooms and some are stronger than others. Consuming a dose you believe to be a weak strain may bring about unexpected and unpleasant effects if turns out to be a different or a stronger variety.


Magic mushrooms can also come in powdered form; sold as capsules or as the powder itself. The dangers of purchasing/receiving psilocybin in this form are greater than the fresh or dried variety. It is far easier to add adulterants to powder which greatly increases the dangers of substances of unknown origin, quality and quantity being mixed into what you believe is pure psilocybin powder.

Consuming mushrooms

It is important to recognise that natural products tend to vary in strength even within the same species and across locations. Psilocybin mushrooms are consumed in many ways, fresh or dried, for example, brewed into a tea, put into food, ground-up or just eaten as they are. As mushrooms are almost entirely water, a dose of fresh mushrooms will weigh around 10 times more than the same dose dried. Microdosing psilocybin has become increasingly popular but there is very little research into microdosing at this stage.

Psilocybin and psilocin are known as psychedelic tryptamines and they have very similar molecular structures to a key chemical messenger called serotonin. Serotonin has some very important functions in our brains and digestive systems, including large influences over-regulating our moods, sleep cycles and stress-coping mechanisms.

Due to this similarity in molecular structure, psilocin molecules activate the same receptors in the brain that serotonin activates, particularly at a specific receptor site known as 5HT2A. This particular receptor mediates many different functions in our minds; like mood, imagination, learning and perception.

A large portion of these 5HT2A receptors are located in cells in the cortex; an area of the brain associated with reasoning and rational thought. These cells are also quite long — they span an area of the brain larger than many other cells and therefore have a wider influence over brain activity.

Psilocin sits into these receptors and activates them, thereby producing the characteristic ‘trip’ of a magic mushroom experience, which can include changes in mood, imagination and perception. Recent research has also shown psilocin has an effect on a part of the brain known as the Default Mode Network (DMN).

Our DMN’s are like our brain’s main information highways. They act as consolidation centres while we go about our daily lives, compiling information quietly in the background. They also allow us to ‘time travel’ in our minds, giving us the ability to think back to the past and plan into the future. Some also theorise our DMN’s are home to our individualities; that they house our senses of ‘self’.

Psilocin temporarily disables one or more of the DMN’s ‘connector hubs’. This temporary shutdown of our brain’s main information highway means the brain cannot connect with the different parts of itself like it usually does, and is instead forced to connect in ways it does not usually. This means the brain starts communicating with parts of itself it doesn’t normally ‘talk’ to, which means the brain creates new connections while under the influence of psilocin.

Our understanding of exactly how psilocin affects the brain is not yet complete, and scientific research continues.

Psilocybin mushrooms produce changes in a user’s consciousness, mood, perception and sensory experience. These changes are classically known as a psychedelic ‘trip’, and can last anywhere between 2–6 hours. The intensity of the trip is directly related to the dose consumed and the strength of the mushrooms in terms of their psilocybin content.

A commonly reported effect is that the mind seems to become more open under the influence of psilocybin and sensory experience can become very intense.

This means things which a person would normally find aesthetically pleasing (art, nature, music etc) can become far more beautiful on psilocybin than when sober, but it can also mean that normal sensory experience can become overwhelming. Being in a crowded place like a street or a nightclub, for example, can become difficult because of the sheer amount of sensory input which can easily overwhelm the mind and the senses. The optimum physical setting for a psilocybin mushrooms experience is somewhere comfortable and familiar, where the amount of sensory input is low or can be controlled, like at home or in a peaceful open space.

Key effects of the experience include thinking in new, interesting or peculiar ways; having emotions far more connected to sensory experiences; having your gaze directed inward toward your own emotions or character; experiencing time distortions; experiencing visual and auditory hallucinations; and, at very high doses, experiencing ego death.

Given that psilocybin seems to connect parts of the brain in novel and interesting ways; different, fascinating, odd and sometimes scary ways of thinking can present themselves to the user. There is little one can do to predict the ways a psychedelic trip will go, and the best practice is to ensure a positive mindset and comfortable setting prior to the trip.

Hallucinations can occur based on the strength, type and dosage of the magic mushroom consumed and can include changes in perception of sounds, closed-eye visuals and open-eye visuals.

Closed-eye visuals can range anywhere from seeing fractal patterns and vivid colours to experiencing dream-like sequences and deeply-set memories, all with your eyes closed. Open-eye visuals can include hallucinations of your environment, like colours becoming much more vibrant, surfaces seeming to ripple or ‘breathe’ before your eyes, patterns forming, moving or rotating as you observe and much more. At higher doses objects and environments may morph into different things and you may experience things that are not really there.

Auditory hallucinations can include sounds becoming clearer, crisper or more distorted or layered with meaning. The perception and appreciation of music or words/language can also change.

At very high doses users may experience something known as ego death. This is an intense experience when your sense of self can (seemingly) cease to exist, which can be frightening, strange, or enlightening, or all three. A high dose is not recommended, especially to first time users or those not overly familiar with the trip, as ego death can be a very intense experience.

Psilocybin mushrooms have potential medical uses in the treatment of mental illnesses and disorders such as depression, anxiety, alcoholism and PTSD, and potential therapeutic uses for things like counselling and even grief.

Numerous studies have been carried out (most notably by David Nutt and Imperial College, London) into the usefulness of psilocybin mushrooms, particularly in the treatment of depression. The findings of these studies show a high correlation between controlled psilocybin experiences and the lessening of depression in subjects, sometimes from as little as one psilocybin experience.

Studies have also shown a correlation between microdosing psilocybin (consuming a dose far smaller than that which would produce psychedelic effects) and the treatment of smaller conditions like migraines and cluster headaches. However, there is very little research into microdosing at this moment in time and many believe the effects to be purely placebo.

Medical administration of psilocybin for the purposes of treatment should only be carried out by registered professionals and you should not attempt medical use of psilocybin yourself.

Research on psilocybin therapy continues — for more detailed information on the medical applications of psilocybin, based on clinical trials, click here.

The main risks of psilocybin are experiencing a ‘bad trip’. A bad trip can encompass various negative experiences but can include feeling incredibly uncomfortable within yourself or your environment, not being able to properly communicate with others, and losing touch with reality, among a whole host of other potential factors.

The most dangerous of these is losing touch with reality somewhere which could have dangerous consequences. It can become almost impossible to think or act ‘normally’ under the influence of psilocybin, and if a person is somewhere which requires their mental faculties to stay safe, for example on a busy street, a crowded area or high-up somewhere, there can be a serious risk to life.

HPPD and ‘flashbacks’

HPPD is a very unusual and poorly understood harmful effect of having taken hallucinogenic drugs. There are few or no good quality formal accounts of psilocybin causing HPPD (LSD is more commonly the cause) but it likely to be possible, and could go unrecognised.

It is most often experienced as re-appearance of some of the effects experienced during the previously occurring hallucinogenic drug experience after some time without the drug. In most cases HPPD follows a traumatic hallucinogenic drug experience (‘bad trip’). In some cases, sufferers may feel detached from normality or the world.

HPPD has been reported occasionally as longer-lasting, though complete or partial recovery usually occurs after weeks or months. Lingering HPPD has been associated mostly with LSD rather than psilocybin, and often involves higher doses and drug combinations. This kind of HPPD may occur in people with underlying psychiatric conditions or genetic vulnerabilities, but the evidence is very incomplete.

Compared to legal drugs like alcohol and nicotine, which can cause considerable physical harm to users (risk of harm to health and body from consuming the substance), psilocybin carries a low risk of physical harm.

Psilocybin is generally considered to have a very low potential for physical harm, but the risks associated with the consumption of the drug are significant if not done responsibly. Psilocybin is widely considered to be of low risk to health by the scientific community, but it still has its associated risks.

The main one of these is that given psilocybin can produce a potent hallucinogenic state, those with prior personal or family histories of psychosis, schizophrenia or psychological disorders should steer clear of psilocybin. This is because a psilocybin experience could exacerbate potential symptoms or bring them to the surface.

Psilocybin should not be mixed with any other illicit drugs, alcohol or nicotine. Drug combinations can be unpredictable, dangerous and potentially even fatal.

Psilocybin should not be mixed with any psychiatric medication or any anti-depressants such as SSRIs or MAOIs. Psilocybin molecules are theorised to affect the same neural receptors as some prescription drugs and they should not be mixed to exclude any potential for adverse drug-drug interactions.

Psilocybin mushrooms seem to have a very low potential for addiction in humans. There have not been any significant cases of people becoming detrimentally addicted to mushrooms.

Psilocybin molecules have not been seen to change the supply of any endogenous neurotransmitters, nor do they affect activation of neural receptors through the use of the brain’s existing supply of neurotransmitters (like cocaine or MDMA do).

Instead, psilocybin molecules seem to mediate their effects through activating 2A serotonin receptors while leaving the brain’s existing supply of serotonin untouched. This prevents the potential for upregulation or downregulation of neurotransmitters, and therefore strongly negates the potential for physical addiction.

The body has a high tolerance for repeated use of psilocybin mushrooms. A user consuming psilocybin one day would have a far diminished effect consuming the same amount the next day. The body’s ability to quickly create a high tolerance for psilocybin means there is a low potential for addiction.

Magic mushrooms have relatively low risks to physical health compared to many other drugs because they are not considered addictive and are rarely used regularly. However, tripping on a psychedelic drug has the potential to produce overwhelming and intensely unpleasant experiences.

The best method of staying safe from psilocybin mushrooms is not to consume them at all, but if a person is going to consume them there are some safety practices which should be followed.


  1. Making sure you have the right mushrooms

Psilocybin mushrooms can sometimes look similar to other non-psilocybin mushrooms. Getting psilocybe mushrooms mixed up with other mushrooms can be harmless in the best-case scenario or fatal in the worst-case scenario.

Poisonous varieties of mushrooms do exist in nature and great care must be taken when choosing a type of mushroom to consume. This is especially a danger if a person is picking wild mushrooms without the proper knowledge or guidance.

There are also many different types of psilocybin mushrooms. Some are weaker in effect and some are stronger — even mistaking a strong variety for a weak one can have unintended consequences by making a trip more intense than anticipated.

It is imperative to know what kind of mushroom you are consuming before you consume it. If you are unsure, do not take them or consult a mycologist or someone who is familiar with varieties ad types of mushrooms.


  1. Dosage and Measurement

Dosage is extremely important when taking any kind of substance as dosage directly affects the intensity of a trip and/or health risks of a substance.

As psilocybin mushrooms have a very low potential for adverse physical health risks, taking too high of a dose may not do any physiological harm but it will often cause a very intense, unsettling or uncomfortable experience which could leave psychological damage.

The dosage of psilocybin mushrooms differs depending on whether the mushrooms are fresh or dried. As mushrooms are composed of about 90% water, dried varieties will often have a dosage of 10x less than fresh varieties.

For example, if an average dose of fresh psilocybin mushrooms is 20g, the dosage of the same variety of dried mushrooms would be 2g.

Before consuming any psilocybin mushrooms (fresh or dried) it is very important to accurately weigh them to ensure the correct dosage. Accurate gram and milligram scales are widely available and should be used to ensure the dosage is correct.


  1. Set and Setting

After ensuring you have the correct type of psilocybin mushroom and accurately measuring the dosage, your set and setting has a strong impact on whether you have a good or bad experience.


Set refers to your mindset. A common effect of the substance is the exaggeration of what you are already feeling. A positive mindset or, at the very least, a neutral mindset is key to the psilocybin experience. If a user is in a highly anxious, fearful or in an otherwise negative state of mind before consuming mushrooms, it is likely these emotions will spill over into the psychedelic experience and cause a bad trip. Conversely, if you are in a positive mood the psilocybin is likely to lift that mood and reflect more of what you are feeling, leading to a happy, insightful and even euphoric experience.

If you are in a bad or negative frame of mind, psilocybin may magnify what you’re feeling, which is an almost surefire way to have a bad trip (if you’re not under the supervision of a professional). Tripping on psilocybin mushrooms when in a negative state of mind may lead to strong feelings of anxiety, discomfort, fear or even terror.


Setting refers to your environment. Common effects of psilocybin can range from visual distortions and hallucinations to deep-diving into one’s mind or personality. The substance seems to make the brain open to all and any sensory experience during the trip. This means if you are in a loud, crowded, unfamiliar or otherwise uncomfortable environment it is very likely to lead to a bad trip, even if you begin with a positive mindset.

It is very important to ensure your environment is familiar, comfortable and you are with people you trust before embarking on a psilocybin trip. Not doing so will almost certainly lead to a negative experience.


  1. Tripsitter

It is an idea to have a trusted, sober person present when on a psilocybin trip. This person, known as a ‘tripsitter,’ can ensure everyone is safe, has a positive experience and can deal with any potentially situations which may arise.

Situations like these can include when a user has a bad experience and doesn’t know what’s real or not — the tripsitter can bring them back to reality and ensure them whatever they’re thinking or experiencing is not real and the drug will eventually wear off. Reassuring comments and gestures are helpful, as is making sure those who are tripping are not feeling anxious or uncomfortable.

An ideal tripsitter would be someone who has also experienced positive psilocybin trips. This means they understand the feeling of the trip and what is needed to effectively tripsit. Psilocybin can make users very sensitive to their own moods and the moods of others. Having a tripsitter who is judgemental or does not agree with consuming psilocybin mushrooms will very much negatively affect the experience of those tripping.


  1. Killing the High

Colloquial evidence and user trip-reports suggest the psilocybin high can be cut short or ‘killed’ by consuming sugary foods & drinks like sweets, carbohydrates or fruit juices. It is theorised the sugars break down the psilocin in the blood, speeding up the process of bringing the user back to sobriety/reality quicker.

There is not much scientific evidence to support this theory, but if a user is having a bad trip and/or wants to come down, consuming sugary foods or drinks will not do any harm.

Do Psilocybin Mushrooms cause brain damage?

From the 1960s there was a popular theory that psilocybin mushrooms (and drugs in general, especially hallucinogens) caused permanent brain damage from just one-time consumption.

There is no scientific evidence that this is true, and science does not show one-time or infrequent use of psilocybin mushrooms has any vastly detrimental effects on the brain. In fact, studies have even suggested psilocybin helps create and connect brain cells.

However, there are few studies showing what regular use of psilocybin does to the brain. From this respect, it is best to space trips out (3 months apart, at the least), in order to stay safe but also to maximise the positive outcomes from trips and minimise the building of physical tolerance.

Are fly agaric mushrooms (Amanita muscaria) psilocybin mushrooms?

No. Fly agaric mushrooms (the fairytale toadstools with white spots on red) belong to a different family and should not be confused with psilocybin-containing mushrooms. Rather than psilocybin, the key chemicals associated with the psychoactive effects include ibotenic acid and muscimol. Effects can include twitching, drooling, sweating, dizziness, vomiting and delirium, very unlike the fairly mild physical effects of psilocybin mushrooms. Fly agaric mushrooms do not appear to be a popular recreational drug. In the UK, when the sale of fresh psilocybin mushrooms became controlled, some shops started selling dried fly agaric mushrooms as a non-controlled alternative. However, there is a risk that these types of products might contain a range of added substances, especially when powdered samples are involved. The fly agaric and commercially available products of that nature should not be considered a legal alternative to psilocybin mushrooms as their effects and risks are very different.

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Nitrous Oxide (Laughing Gas) Molecule Chemical Structure

Nitrous oxide (N2O), commonly known as laughing gas or nos, is an anaesthetic gas with pain-relieving and anti-anxiety properties. It has been used recreationally and in medicine for over 200 years. It has become widely and easily available for recreational use as it can be legally bought and sold for the purpose of making whipped cream. However, as of 2016, it is illegal to possess nitrous oxide with the intent to sell for use of its psychoactive properties.

Nitrous oxide is a colourless gas that has a slightly sweet smell and taste. It is usually obtained for recreational use from whipped-cream chargers. These are single use, finger-length steel canisters containing 8g of highly pressurised nitrous oxide. The gas is usually discharged into a balloon with a whipped cream dispenser, or a smaller widget called a ‘cracker’. This balloon method seems to be relatively low risk. Other sources of nitrous oxide include full-sized gas cylinders, intended for medical or industrial use. Using these is high risk outside of the intended context.

The exact mode of action of nitrous oxide is still unclear. However, theories have been put forward to explain its actions. There are three main ways that the body is affected by the compound. Firstly, the anti-anxiety effect is produced by the blocking of neurotransmitters by GABAA receptors. Secondly, it has been suggested that the analgesic effect is due to the stimulation of opioid receptors, resulting in the release of norepinephrine, which inhibits pain signalling throughout the body. Finally, the euphoria felt when the drug is taken is due to the release of dopamine triggered by stimulation of the brain’s reward pathway.

The recreational effects occur at lower concentrations and may be produced by alterations in brain blood flow such as are believed responsible for the recreational effects of another gas, nitric oxide, which is produced from the sniffing of “poppers”.

When someone inhales nitrous oxide, the gas rapidly dissolves into the bloodstream, and reaches the brain within seconds. A rush of dizziness and euphoria is commonly reported, and people often burst into laughter. Sound distortion also occurs.

Hallucinations are possible, from simple moving bright dots to complete detailed dreamscapes, although most users do not experience complex hallucinations. Due to the anaesthetic properties of the gas, coordination and awareness are strongly affected, and users may fall over if they are not sitting or lying down. The effects are short lasting, wearing off within two minutes. Nitrous oxide also reduces anxiety and pain.

Additionally, when purely nitrous oxide is inhaled recreationally, the gas displaces air in the lungs, temporarily preventing much or any oxygen from reaching the blood. This may cause the heart to beat faster, and limbs to feel tingly or heavy.

Nitrous oxide has a long history of medical use, particularly during dental treatment and childbirth. It is used as an anaesthetic, for pain relief, and to relieve anxiety. It is also administered to patients in ambulances and used in emergency departments. In this context, the gas used is typically a 1:1 mixture of oxygen and nitrous oxide.

Using nitrous oxide is relatively low risk, however, it is still very important to be aware of the risks involved, and what you can do to avoid or reduce them.

Oxygen starvation
Inhaling nitrous oxide prevents oxygen from entering the lungs and therefore the bloodstream. This can lead to oxygen starvation which can be fatal when extreme. Some methods of inhaling nitrous oxide can increase the risk of experiencing extreme oxygen starvation. For example, inhaling directly from a canister; inhaling in an enclosed space; placing a bag over one’s head to inhale; filling a room with the gas; or using a medical mask to inhale.

When the gas is released from its highly pressurised container, the gas and metal briefly become very cold (around -40°C). Exposure of tissue to this extreme cold can result in frostbite. Therefore, it is important to take care when opening a canister, and important to not inhale directly from the canister, as this can cause frostbite of internal tissues.

Injury from falling
As inhaling nitrous oxide causes dizziness, it is possible that people may lose balance and fall after inhalation, leading to injury. To prevent this, nitrous oxide should only be inhaled when sitting or lying down.

People with heart conditions or abnormal blood pressure may be at higher risk as the drop in oxygen levels caused by inhaling nitrous oxide raises the heart rate and can cause arrhythmias (skipped heartbeats). This could lead to cardiac arrests in susceptible people.

As with all drugs, mixing nitrous oxide with other substances increases the risks. Therefore, it is not advised to mix nitrous oxide with any other drugs, especially alcohol. It is possible that risks could be greater with stimulants and any other drugs that put pressure on your heart, as effects on blood pressure and heart rate could be unpredictable.

Nitrous oxide can, allegedly, briefly multiply the effects of psychedelics like LSD (acid) and psilocybin (magic mushrooms), or bring the effects back strongly when the drug is wearing off, which could be very frightening if unexpected.

Due to the short-lasting effects of nitrous oxide, people are often tempted to take multiple doses over a short period of time. It is possible for people become psychologically addicted to nitrous oxide and find it difficult to resist taking it every day. Those with existing mental health conditions may be at additional risk of addictive behaviours.

Regular heavy use of the drug can lead to vitamin B12 deficiency. As vitamin B12 is essential for maintaining the nervous system, abuse of nitrous oxide can lead to nerve damage. Symptoms of nerve damage include tingling and numbness in fingers and toes and weakness of the arms and legs. Treatment with high doses of B12 is effective, but some damage can be irreversible. It is likely that less severe vitamin B12 deficiencies caused by nitrous oxide overuse can go undiagnosed, but cause other symptoms, such as depression, forgetfulness, and tiredness.

Using a balloon
Using a balloon, with caution, is the least risky way to use nitrous oxide. Here, the gas is dispensed into a balloon from which a user inhales and exhales repeatedly until they have inhaled enough, or the gas runs out. If oxygen levels in the body drop to the degree where the user is close to losing consciousness, they will be unable to hold the balloon to their lips and will automatically begin to breathe air again. This safety mechanism minimises the risk of death by suffocation. Paying attention to any discomfort and not resisting the urge to breathe normal air will minimise the chances of harm of any kind.

Choosing the right setting
The risks of getting hurt if you fall or lose coordination and awareness when taking nitrous oxide can be minimised by sitting down away from hard edges and other hazards.

Never try to fill a space with the gas
Never attempt to fill a room, car, bag over someone’s head, or any enclosed space with nitrous oxide. This can lead to fatal oxygen starvation.

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Methoxetamine  is a powerful dissociative drug in the same family as ketamine and PCP (arylcyclohexylamines). It is a new drug and there has been very little research into its effects and dangers, so the information in this article is more provisional and less definitive than the other articles on this site.

Like ketamine, methoxetamine is usually acquired as a whitish powder. However, compared to ketamine, a much smaller amount of methoxetamine is required to produce the desired effects, and it is very easy to take too much.

Methoxetamine has also been identified in powders containing other drugs, including mephedrone and cocaine. It has also been found mixed with other drugs in tablets.

Very little is known about methoxetamine. It is a ‘dissociative anaesthetic’, working in similar ways to its close relatives ketamine and PCP. It seems to affect several different receptors in the brain.

Methoxetamine has no known medical uses. However, ketamine has existing medical uses, so drugs in this family are beginning to be investigated by scientists looking for useful properties such as antidepressant effects.

Little is known about methoxetamine so the risks of trying to self-medicate with this drug are likely far to outweigh the chance of benefits.

Our knowledge of the effects is currently based on the unconfirmed reports of users and a handful of case studies from hospital admissions and is therefore unreliable and incomplete. Methoxetamine seems to share similarities with the effects of ketamine, although it seems stronger and much longer lasting than ketamine.

•Smaller doses are reported by some to produce euphoria and fuzzy, floating, cosy feelings.  It seems to make people chatty or relaxed.

•Higher doses can bring increasingly strange feelings of disconnection from normal reality. It becomes increasingly difficult to talk fluently, but thoughts may seem exceptionally meaningful. Alternatively, users report feeling unpleasantly confused. The body may feel clumsy, uncoordinated and detached from the mind. Vision and hearing may become juddering and impaired.

•A high dose can cause a full-blown ‘trip’ or ‘M-hole’ with hallucinatory visions. There may be unpleasant confusion and anxiety, and there have been reports of users getting agitated and even aggressive. Users may become unresponsive to people in the outside world, and physical effectsincreasing the heart rate and blood pressure may be risky. The visions experienced can be very realistic and seem fun, scary or even spiritual, but they are unlikely to be remembered in detail. High doses will seriously impair coordinated movement but some have reported that it is more possible to stagger around (and therefore to injure yourself) on a high dose of methoxetamine than on a high dose of ketamine. According to some users, the long-lasting effects make it more likely that a powerful experience will feel unpleasantly draining.

Reported unpleasant effects include nausea and vomiting, dizziness, headaches afterwards, and difficulty sleeping which can last days. Some users can show signs of impairment for days, or feel slow-witted for hours after any pleasant effects have finished. Low doses probably have a lower risk of serious and lingering unpleasant effects.

A major risk of taking methoxetamine is that there is so little known about the risks of taking methoxetamine.

Some of the problems that have occurred resemble the problems that can be caused by ketamine. Patients admitted to hospital after taking the drug showed raised heart-rates and blood-pressure, and some were experiencing hallucinations and disorientation, agitation, fear and confusion. Based on the very small number of patients reported, the symptoms appear generally more severe than is common with patients who are admitted to hospital after taking ketamine. These acute symptoms are reversible.

What may appear a small quantity may be enough to cause collapse, and even an ambulance ride. Measuring by eye rather than using sensitive scales is very risky. Unpleasant or harmful effects are likely if people take a similar quantity as they are used to taking of ketamine.

Like ketamine, the greatest risk of serious harm or death from methoxetamine may be accidentscaused by the effects of the drug, (especially when combined with other drugs like alcohol) such as road accidents or falls. Anecdotal evidence suggests that it is easier to remain mobile after taking large amounts of methoxetamine compared to large amounts of ketamine. This could increase the risk of injury. This risk can be reduced by preparation of a safe area and the presence of a sober friend.

Aside from the risks of physical harm, the risk of having an unpleasant or even a traumatic experience should be taken seriously. Online user reports of overdoses and bad trips cannot be verified, and it is impossible to know how representative they are of users’ experiences. However, taken as a whole they build up an image of a drug that is capable of causing very frightening and overwhelming experiences, even in experienced drug users. The long duration of the drug’s effects increase the significance of this risk. As with all mind-altering drugs, the chances of a horrible trip are influenced by the ‘set and setting’. Taking methoxetamine when in a low mood, in a stressful unfamiliar place, amongst strangers would be more likely to be disastrous.

There is no relevant evidence about methoxetamine. It is likely that the risks could be similar in many ways to those of ketamine.

It is virtually certain that, like ketamine, methoxetamine will be much more harmful when taken with nervous system depressant drugs like alcohol, heroin or GBL. Combining these drugs powerfully amplifies their negative effects on risky behaviour, consciousness, movement and breathing. One individual needed a tube to keep his airway open so he could breathe after taking the drug with alcohol. Two deaths by drowning that have been linked to methoxetamine also involved alcohol.

The effects of methoxetamine on heart-rate and blood pressure are likely to be exacerbated by stimulant drugs like cocaine and amphetamines, and the risks of disturbing visions and panic may be raised by mixing with cannabis or hallucinogens.

We have no solid evidence. Methoxetamine is related to ketamine, which can be addictive. The reports of users on the internet indicate that some people consider themselves addicted and suffer significant damage to their quality of life from this.

Because it has been around for such a short time, we have no evidence of long-term harms. It was claimed by people selling the drug that methoxetamine is an alternative to ketamine without the risks to the bladder that ketamine has, but there is no evidence for this whatsoever, in fact it appears todamage the bladders of mice.

If, like ketamine, it is addictive, (and unconfirmed user reports online support this), then persistent use could lead to serious effects on people’s quality of life. Addicted ketamine users suffer cravings that disrupt their lives and the drugs can cause negative effects on memory. Regular users can regularly feel a bit befuddled. These mental effects seem to reverse when users quit the drug.

Because so little is known about it, there is an argument that taking methoxetamine is always unacceptably risky. Even so, if you do use the drug, there are ways of reducing the chances of getting harmed.

Be extremely cautious with the dosage

•A line or a pinch measured by eye is probably too much. Digital scales which measure at the 0.001g (1 mg) level may help you prevent errors and can be bought online.

•Users report that methoxetamine can take an hour or so to really kick in. If you add to your dose at this point, the combined effects may be stronger than anticipated.

Avoid mixing it with other drugs, especially alcohol

•It is almost certain that, like ketamine, methoxetamine will be much more harmful when taken with alcohol. Combining these drugs powerfully amplifies their negative effects on risky behaviour, consciousness, movement and breathing. Two deaths by drowning that have been linked to methoxetamine also involved alcohol.

Be prepared

•A reckless decision to take methoxetamine among strangers in a chaotic party is likely to result in an unpleasant experience.

•The chances of having a messy experience can be minimised by staying at home, measuring out doses beforehand, and getting comfy on a bed or sofa with someone sober to chat with who you trust to look after you if needed.

•Leave plenty of time for recovery and sleep before you have anything important to do.

Watch out for the possibility of addiction

It is likely that, like ketamine, tolerance builds up rapidly, so a regular user needs more and more to get the effects they want. The more you use, the higher your risk of suffering cravings and symptoms if you try to stop, and so becoming addicted. If your tolerance is increasing, be especially mindful of the risks of addiction.

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Methadone is a prescription only medicine that can be taken orally and is used mainly to treat opioid addiction. Is was initially developed as a painkiller but now it is much more widely used to treat people who have got stuck on heroin or other opioid drugs (such as prescription painkillers). Methadone is a powerful opioid drug, so it has similar effects to drugs like codeine, morphine, and heroin. It lasts much longer in the body than heroin, and therefore it is used to stabilise people currently using heroin (or other opioid drugs) and then help them get off opioid drugs completely.

Methadone should not be confused with mephedrone, they are completely different drugs. Anyone taking methadone when they are looking for mephedrone risks extreme danger.

Methadone usually comes in liquid form that can be swallowed. It is usually a green liquid although there is a blue liquid that is much more concentrated. Methadone also comes as tablets but this preparation is rarely used.

Methadone is used illicitly, there is a street value for methadone that has been diverted from medicinal use. Most people use it illicitly in the same way as prescribed. As methadone is a powerful opioid drug it is very dangerous for people who are not tolerant to opioid drugs.

Methadone is an opioid drug. It mimics the body’s natural pain-killing chemicals, endorphins. Therefore it can relieve pain, cause drowsiness, can cause mild euphoria, slow breathing, slow the bowels causing constipation, and cause other side effects of opioids.

Yes. It is mostly used as a substitute medication for people addicted to opioids such as heroin. It is occasionally prescribed as a pain-killer.

As an opioid, it mimics the body’s natural pain-killing chemicals, endorphins. Therefore it can relieve pain, cause drowsiness, can cause mild euphoria, slow breathing, slow the bowels causing constipation, and other side effects of opioids. As it takes longer to build up in the body and takes longer to come out of the body it causes much less euphoria than heroin. However, most people report being drowsy, mentally slowed, and often a bit sweaty taking methadone every day.

If someone takes an overdose of an opioid drug they can die quickly. This is usually by respiratory depression (slowing the drive and effectiveness of breathing). Anyone not used to opioid drugs would be much more at risk of this. Methadone is often reported as a contributory cause of death in opioid drug related overdoses. It is particular dangerous if mixed with other drugs such as heroin, alcohol, and benzodiazepines.

The risks of death by overdose increase when many substances are taken together for example alcohol and benzodiazepines which also have effects on breathing (respiration). Methadone decreases control and impairs judgment, making the risk of accidents much higher. This means activities like driving under the influence of methadone are potentially very dangerous. If you are prescribed methadone by your doctor you must inform the DVLA and they have to make a decision whether you are still safe to drive.

The risks of depressed breathing caused by methadone may be increased in people with conditions such as muscle weakness (e.g. myasthenia gravis), sleep apnoea, or lung disease/breathing disorders.

Methadone is dangerous if mixed with alcohol, benzodiazepines or heroin. Taking methadone with depressant drugs increases the risk of depressing breathing. Additionally, the effects of methadone may be masked if taken with a stimulant, which can lead to an overdose if a lot of the drug is taken and then the stimulant wears off. Certain medications (e.g. some antidepressants) may also interact with methadone to increase sedative effects.

One-off or occasional use of methadone is very unlikely to result in the development of depend-ence. However, taking methadone regularly over a sustained period can cause serious physical and psychological addiction. People who become dependent on methadone may become tolerant to the drug’s effects and experience withdrawal symptoms without it. Users may crave the drug and feel unable to cope without it. The longer the drug is taken, the higher and more regular the dose and the stronger the methadone, the higher the risk of dependence.

A period of sustained dependence on any drug can be debilitating and prevent people from working and leading an active life. It may also cause mental and physical harm and opioid withdrawal can be very unpleasant.

Acute withdrawal effects from methadone can be intense, although for many they will be milder than those from heroin. Acute withdrawal effects include shivering, yawning, feeling cold and clammy, goose-bumps on the skin, diarrhoea and vomiting, flu-like symptoms, agitation, anxiety, insomnia and sensitivity to sound/light. Opioid withdrawal symptoms are unpleasant but do not endanger life.

Potential effects of long term methadone use include constipation, tiredness, sedation. People often have problems with their teeth as methadone reduces your natural saliva which protects the teeth against dental caries.

Long-term risks of methadone are low if it is used as prescribed.

How much are you taking? How often?

If taken according to prescription then methadone is very safe.

Are you taking it with anything else? Mixing drugs is risky.

Mixing with benzodiazepines and alcohol is potentially very dangerous. Also if other opioid drugs are used, although initially methadone would usually block the effects, eventually you can over-whelm the methadone and accidentally overdose.

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Mephedrone (4-methylmethcathinone) is a former legal-high that is now banned across the EU. It is a manufactured substance rather than natural substance.

It appears as a white or off-white powder which is primarily either snorted or swallowed. Injection has also been reported. Injection of drugs is associated with higher risks of overdose and other harms like infection.

Mephedrone is a stimulant and its effects are reported to be similar in some ways to cocaine and MDMA. As mephedrone has only been widely used from around 2009 onwards, not much has been established scientifically about the specific effects of the drug.

People who have used mephedrone report stimulant effects such as increased energy, self-confidence and talkativeness. Reported effects also include feelings of empathy/closeness to other people, which is why mephedrone is sometimes said to be like MDMA. However, most users report that mephedrone’s effects are noticeably different to those of MDMA, being more stimulant-like and lacking the full extent of MDMA’s sensual, empathy-promoting properties.

When mephedrone is snorted, it only takes a few minutes for its effects to appear, and the effects generally peak in half an hour or less. When swallowed (usually wrapped in a cigarette paper) its effects can take more than 45 minutes to appear, depending on factors like how much food is in the stomach.

Some people have unwanted side effects of the drug such as: loss of appetite, muscle clenching and tremors, headache, anxiety, elevated blood pressure and chest pain, fast/irregular heartbeat, difficulty urinating, changes in body temperature (hot flushes and sweating) and blue/cold fingers.

People using the drug also report a comedown period after use, which can also be compared to the comedown periods experienced after cocainespeed or MDMA use. Users have reported that it is very tempting to take more mephedrone again and again to keep the high going and to prevent the comedown. This increases the risks of immediate harm and may increase the risk of becoming addicted. (Much of the information in this section was taken from Schifano et al, 2010).

There have been deaths associated with or caused by mephedrone use, although not as many as were reported in the media. Usually, deaths involved very high doses, mephedrone use with alcohol and other drugs (including interacting prescription drugs) or pre-existing problems such as heart or liver conditions.

Mephedrone deaths and serious emergencies occur in a similar way to deaths from other strong stimulants. The drug effects can overload the heart, and overheating can cause seizures and organ failure. Fatal accidents have also been associated with the drug.

It should always be treated as a medical emergency if someone collapses having taken mephedrone, suffers seizures, or sudden chest pains.

Other much more common nasty effects, usually associated with moderate or high doses, include feeling unbearably hot, feeling faint or that your heart is racing uncomfortably fast. Some people suffer paranoia, frightening hallucinations, confusion, panic and agitation. If you or a friend gets these symptoms, stay as calm as you can, move if necessary to a more relaxed, cooler environment and try to calm down. Lying down may be helpful, taking slow breaths, (breathing in and out of a paper bag helps with panic). If this doesn’t help, it may be necessary to get medical help. If it does help and you feel totally recovered, it is still sensible not to get back into the party and take more mephedrone.

Some people have binged on mephedrone for several days. Eating, drinking, sleeping and resting are vital. Missing these things makes someone more likely to suffer from any of the potential harms, from the slightly unpleasant effects to seizures, psychosis and death.

As with other stimulants such as speed or cocaine, taking mephedrone if you have a heart problem or high blood-pressure is likely to be riskier.

Mental health should be taken into account, as the chance of panic, paranoia, hallucinations and compulsive bingeing are likely to be increased if you have a disorder that predisposes you to these.

The risks of harm, including death, are likely to be increased by taking the drug whilst being on prescribed medication (especially antidepressants) or particularly taking other stimulant drugs such as amphetamines, MDMA and cocaine.

Not enough is currently known about mephedrone to say how harmful use would be over a long period of time. It is probable that the long term harms of mephedrone would be similar to drugs such as cocaine and MDMA due to their similar effects and structure. There is also some suggestion that mephedrone could be quite addictive, with cravings and low mood unless the drug is taken. However, there has not yet been enough rigorous scientific investigation into mephedrone addiction.

Mephedrone harm reduction advice is partly based on what we know of related drugs like amphetamines and MDMA, as not enough research has been done on mephedrone specifically.

• Taking it with other drugs increases the risks

• Deaths related to mephedrone usually involve large amounts of other stimulants such as cocaine, or depressants such as alcohol.

• You may overheat when taking the drug

• Mephedrone reportedly causes increases in body temperature. If you are dancing also you may overheat and become dehydrated. It is therefore a good idea to take regular breaks from dancing and drink moderate amounts of water.

• Tolerance is a bad sign

• As with most drugs, becoming tolerant to its effects is a sign that your brain chemistry is being changed by the drug, and that you are at high risk of addiction.

Is it actually plant food or bath salts?

Before mephedrone was made illegal, people would sell mephedrone as plant fertilizer, bath salts or as a research chemical. This was a disguise for selling it for use as a recreational drug, to get around the law. Mephedrone cannot be used as plant food/fertilizer or as bath salts.

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chemical structure of mdma molecule, the active compound in the stimulant drug ecstasy

MDMA (ecstasy) is a drug that produces feelings of euphoria and empathy along with energising effects similar to amphetamine. It is commonly sold either in pill form (known as ecstasy) or as MDMA crystals. Please use the drop-down questions below to learn more.

If you are an ecstasy user, please read our PMA harm reduction guide.

MDMA is often taken in pill form (‘ecstasy’ pills). In the last decade however, there has been a shift towards MDMA being sold as a powder, which often looks like crushed up, off-white, brownish or yellowish crystals. MDMA powder can be swallowed, dissolved into a drink or snorted.

Pills or powders sold as ‘ecstasy’ or MDMA cannot be relied on to contain any MDMA. Often pills or powders have other drugs and fillers mixed in, such as the drug PMA. This can make things much riskier. The designs on ecstasy pills are not a good guide to their safety and reliability as pills with a ‘good reputation’ can have their designs copied.

The quantity of MDMA in pills and powders varies all the way from 0% (e.g. pills made of plaster of Paris) to close to 100%, so you can’t guide your dose reliably by the amount of powder or number of pills. This means that users can accidentally take more than intended. A single pill can contain enough MDMA to make some people feel overwhelmed, and on occasion pills and capsules have appeared which have contained quite dangerous amounts in one unit. Someone accustomed to taking several weak pills can overdose if the purity increases.

The popularity of MDMA powder is in part a reaction to the suspicion people have of pills. However, PMMA and other potentially harmful substances have been found in both pills and powder. Neither type can be relied upon to be unadulterated, or to contain a fixed dose.

MDMA is a stimulant (it is structurally similar to amphetamine) that can give feelings of energy and exhilaration. Unlike typical stimulants though, it also produces distinct social and emotional effects, and alters perception. Because of this some scientists have proposed that it should be classed as an ‘entactogen‘. Compared to other stimulants, MDMA is particularly powerful in releasing a brain chemical called serotonin. This seems to affect many systems in the brain, usually boosting mood, and sometimes producing slightly psychedelic (‘trippy’) changes in perception. MDMA also has the effect of increasing levels of the hormones oxytocin and vasopressin, which may be involved in making users feel emotionally connected. All these enjoyable effects of MDMA are potential sources of risk too. The effects of excess serotonin or vasopressin, or too much stimulation are among the reasons that MDMA occasionally causes harm and death.

How soon the effects of MDMA are felt depends on the method in which it is taken. Swallowing an ‘ecstasy’ pill or MDMA ‘bomb’ (MDMA powder wrapped in a cigarette paper) may result in a time lag of 20 minutes to an hour before the effects really kick in. Effects peak around 2 hours after a pill is swallowed.  If a pill is in fact mostly or all another drug like PMMA (which can cause fatalities in moderate to large doses), effects may take longer to come on, so taking more to boost the effects without waiting is risky. Snorting MDMA crystal/powder allows for much quicker absorption into the bloodstream and so the effects are felt much sooner but do not last as long.

The effects of MDMA when swallowed last several hours. Although everyone reacts differently, the typical effects reported following a dose of MDMA can be described as follows:

  • Increased energy, alertness and wakefulness.
  • Higher body temperature, heart rate and blood pressure (especially when dancing)
  • Lower aggression and anxiety (though anxiety can sometimes increase in some people).
  • Lifted mood or euphoria.
  • Increased empathy and sense of intimacy with others.
  • Perceptual changes: heightened sense of colour; blurred vision.
  • Muscle clenching, especially the jaw.

Anecdotally, it seems that taking very high doses of MDMA may only increase the energising speed like effects of MDMA, not the euphoric or emotional effects. Unpleasant effects, like anxiety, feeling unbearably hot, over-stimulated, confused or anxious are more likely the more you take.

Very rarely, heart attacks, strokes, and other medical emergencies can be brought on by MDMA, especially in people with pre-existing health problems, or who take it in big amounts and mix it with other drugs.

MDMA  makes people feel thirsty and users can get dangerously hot if dancing non-stop. Some users have collapsed and even died from overheating and dehydration. In attempting to counter these problems a few people have also died from drinking too much water. MDMA affects the body’s ability to urinate out excess water, so too much water can cause the blood to become overly diluted, which can cause death (hyponatraemia). A much more common downside to MDMA is that its effects can be overwhelming, which can cause some people to become panicky.

Following MDMA use, there can be a comedown period which may last several days. In this period users may experience the following:

  • Depression.
  • Fatigue.
  • Anxiety.
  • Impaired concentration.
  • Loss of appetite.
  • Insomnia.

Currently, MDMA has no medical uses.

A small initial study with individuals with Post Traumatic Stress Disorder (PTSD) has indicated that MDMA has potential uses in facilitating and supporting psychotherapy. One idea is that MDMA makes it easier for them to confront memories that they find hard to think about without severe emotional responses.

At present, MDMA cannot legally be used in psychotherapy and clearly much more research is needed to explore MDMA’s potential values and drawbacks as a therapeutic aid.

MDMA is not itself the treatment, but it is proposed that it enables therapy to be possible or more effective. Attempts to self-treat with MDMA could do more harm than good in the absence of a professional therapist trained in MDMA psychotherapy.

Some people taking MDMA have died following severe overheating and other medical emergencies. Deaths following the use of MDMA usually involve high doses and/or the simultaneous use of other substances. MDMA overdoses and drug combinations can also cause serotonin syndrome, which can be fatal. MDMA-associated deaths may alternatively involve overcompensation of the risk of dehydration by drinking much too much water, which coupled with the fact that MDMA may stop a person from urinating, causing fatally low concentrations of salt.

Many people feel depressed in the days after taking MDMA.

Yes. MDMA increases heart rate, body temperature and blood pressure which puts strain on the heart. If someone has health problems like a heart condition or high blood pressure, they will be at higher risk from the drug. Similarly, if someone’s kidneys or liver are not at full health, the risks of using MDMA could be higher.

Take your fitness and general health into consideration. Being unfit will mean that your body will be under greater pressure from MDMA.

Drugs that act on the brain will interact in ways we do not yet know, potentially leading to unpredicatable problems. Many MDMA-related deaths happen when it is mixed with other drugs. Problematically, some pills or powders themselves may be made of a mixture of drugs. Alcohol can contribute to dehydrating when mixed with MDMA, and can dull the effects of stimulants, which combined with the poor judgement that alcohol causes, could lead to someone taking a more dangerous amount of MDMA.

Additionally, if someone is taking certain medications such as antidepressants or even herbal supplements that affect serotonin, there is an increased risk that taking MDMA (even several days afterwards) could cause too much serotonin to collect in the brain (serotonin syndrome) which is potentially fatal.

Serotonin syndrome can also be caused by MDMA mixed with other stimulant drugs.

MDMA is generally considered to have a low potential for addiction, especially when compared to drugs such as alcohol, tobacco or heroin. Although users may report a strong desire to take the drug, they are generally able to stop use if they feel that it is negatively affecting their lives. However, in some cases people have found it difficult to control their use.

A very relevant thing that stands out in the science concerning MDMA, is that studies using people with a history of light and occasional use of MDMA are far less likely to show mental deficits compared to studies where people have a history of binging on large amounts of MDMA or regular MDMA use. Whether or not deficits are caused by lack of sleep or use of other drugs, it is still the case that partying too hard may affect your mental abilities.

There is scientific controversy over the long-term harmful effects of MDMA. Although, studies with MDMA users have found impairments in memory and impulsivity, there are other factors which may contribute to this, such as use of other drugs and lack of sleep. Controlling for such things, one particular study found no significant connection between MDMA use and performance on cognitive tests, although this study has received some criticism.

It is also possible that something like impulsivity could make someone more likely to take MDMA, rather than being caused by drug use (summarised in this article). A similar confusion is found with the link between MDMA and depression. Some studies have suggested that MDMA can contribute to depression, though some have found that those with depression may be more likely to later take MDMA.

Whether such effects would last for a very long time is also debatable. There is strong evidence from brain imaging studies suggesting that most changes in the brain areas affected by MDMA (serotonergic system) are not long term.

For most people, it is hard to know what to think when considering the possible long term harms of MDMA. One thing that you need to consider, is that a statistically significant effect on memory in a study, may reflect a very subtle (but possibly significant) effect on everyday life. Effects being subtle however, may also mean that effects on mental abilities caused by MDMA could go unnoticed. It is therefore very difficult to know if MDMA would affect you, or whether such effects would be a problem. Additionally, although the long term effects of MDMA may be less risky than something like tobacco, there is no way to know if what is bought illegally is actually MDMA.

There is also anecdotal evidence that after multiple uses of MDMA, the ‘magic goes’ and users no longer find the drug as enjoyable (although this is not reported by all).

How much are you taking?

Higher doses are more likely to cause immediate or lasting harm, as well as unpleasant after-effects. Higher doses are also more likely to cause unpleasantly overwhelming experiences especially in people using the drug for the first time. Some people may feel the effects of MDMA more strongly than others or simply dislike the effects of the drug. If you do decide to take a pill or some powder you should always first take a smaller dose then wait at least two hours before deciding if you really want to take more. If you don’t wait, you could end up taking a very high dose. You should note that some pills may be strong enough for one to be too much, so some people take part of a pill.

Do you know what you are actually taking?

It is common for substances that are meant to be MDMA to be another drug or mixed with different substances. This is a problem because other drugs sold as MDMA may differ in terms of the strength of effects or the amount of time they take to kick in. It is also possible that a pill or powder will contain a very different drug such as ketamine. In this case the effects will be very different from what you expect. What you are sold may also contain non-mind altering substances that could be harmful.

Are you drinking too much or too little water or overheating?

If you are dancing on MDMA, especially in a crowded place, you are likely to get hot and dehydrated. To avoid overheating and dehydration many people taking MDMA drink plenty of water. However, MDMA can also stop you from urinating as much and could affect your perception of how hydrated you are. This means you could end up drinking too much water, which when taken to an extreme is dangerous.

It is therefore a good idea to drink moderate amounts of water and maybe have some salty snacks if you think you have drunk too much. Isotonic sports drinks are helpful for reducing the risks from drinking too much or too little water. It is also a good idea to avoid other things that can make you dehydrated, such as alcohol.

Does MDMA put holes in your brain?

MDMA does not put holes in your brain. This myth comes from messages broadcast by anti-drug campaigns in the late 1990s/early 2000s.

Is MDMA (ecstasy) powder purer than ecstasy pills?

Like most illegal drugs, the purity of MDMA changes all the time, so forms that might once have been more reliable cannot be guaranteed to remain so. It is quite easy for drug dealers to mix MDMA powder with any substance that looks like it, so taking MDMA powder does not necessarily mean you are not unknowingly taking other substances mixed with the drug.

Does MDMA (ecstasy) drain your spinal fluid?

No. This myth probably comes from experiments where researchers measured breakdown products of serotonin in the spinal fluid of animals who had taken MDMA. MDMA does not damage your spine.

Does MDMA (ecstasy) cause Parkinson’s disease?

MDMA does not cause Parkinsons. This myth may come from an experiment where researchers accidentally gave methamphetamine (crystal meth) to laboratory monkeys instead of MDMA. There is a horribly toxic chemical with a four-letter acronym, MPTP, which does cause parkinsonism. It has appeared as an unwanted impurity in a heroin-like (opiate) drug called MPPP, causing the people who took the contaminated drug to ‘freeze up’ by destroying dopamine neurons in the brain, just as Parkinson’s disease does. Neither MPTP or MPPP have any relation to MDMA.

Support our work and help ensure that evidence-based research can influence policy and public opinion, not political or commercial agenda.

Drug Science is an independent, science-led drugs charity. We rely on donations to continue to promote evidence-based information about drugs without political or commercial interference.

We are grateful … But we need more. We can’t do it alone. Becoming a donor will help ensure we can continue our work. Join our Community and access opportunities to become more deeply engaged in our work.

LSD is short for d-lysergic acid diethylamide. LSD itself is not found naturally, but is considered semi-synthetic, as it was first prepared by Albert Hofmann by altering a molecule found in the ergot fungus. Hofmann discovered its unexpected properties when testing it on himself in 1943.

LSD usually comes in little paper squares (blotter) which have been soaked in tiny quantities of LSD solution and dried. Instead of paper, LSD has also been found in coloured gelatine pieces (gel tabs), tablets or very tiny pills called microdots. Once common was the use of sugar cubes which had a drop of LSD solution put on them. Alternatively, a solution can be directly dropped onto the tongue from a dropper bottle. When dealing with an actual LSD solution, there is a risk of taking much more than intended.

However it comes, the drug is held under the tongue and/or chewed. Few people would want to take LSD very regularly, people usually take it seriously and treat a trip as an infrequent and special experience.

Sometimes, doses of ‘LSD’ have turned out to be other chemicals such as the NBOMe drugs. This is a serious problem, because taking too much of these is much more dangerous than taking too much LSD, and could even kill.

LSD is a psychedelic lysergamide hallucinogen. How LSD produces its psychoactive effects is very poorly understood, partly because the action of LSD is so diverse. However, the psychoactive effects of LSD in humans shares many key features observed with psilocybin (magic mushrooms) and mescaline (e.g. peyote cactus). Studies have hinted that psilocybin might suppress the connectivity between brain areas, perhaps changing the way sensory information is filtered by the brain.

As it stands much more research is needed to fully understand how LSD and other hallucinogenic drugs produce their psychoactive effects.

LSD (as well as other hallucinogens like psilocybin) does not necessarily produce a selection of fairly predictable, repeatable sensations and effects like some drugs that belong to other classes such as stimulants. LSD produces a psychedelic experience, often called a ‘trip’, and no two LSD ‘trips’ are the same.

Some people have reported the psychedelic experience to be one of the most intense experiences of their lives. LSD experiences might well be experienced as positive, frequently ‘mystical’, and personally meaningful (and usually draining). However, overwhelming experiences of this nature can be miserable or terrifying too, with horrible effects which may last anywhere from a few moments or several hours.

LSD does not kick in straight away but effects usually come on within an hour. The peak of the trip might last for over 4 hours, with decreasing effects continuing for up to 12 hours afterwards.

With LSD, some people have become anxious, panicky and confused (especially if a very large dose has been taken). Occasionally, a trip can be traumatising.

Passing unpleasant moments are common during a strong trip. Long-forgotten or traumatic events might come to the surface. Longer lasting horrible effects are usually the result of an inappropriately high dose, an inappropriate setting (see ‘set’ and ‘setting’ below), anxieties and other negative emotions present in the user’s mind-set, or pre-existing mental health issues. Even so, it is also possible for unpleasant experiences to happen for no apparent reason, even if the user is well-prepared.

A big enough dose of LSD will produce a powerful psychedelic experience where how you think, see and feel is radically altered. Even with small doses people may experience hallucinations such as patterns on wallpaper moving, and changes in the way they think. Like all drugs a larger dose of LSD will produce a more intense effect. However, due to the high potency of LSD and the varying amounts present in a particular product, it is very difficult to measure how big an effect the drug will have.

More so than other drugs, an individual’s expectations and choices strongly affect the experience.

The experience is often emotionally, physically and mentally draining, and it is common to feel worn out for a day or so after use.  Some feel detached or even alienated from reality. Some report feeling fuzzy-headed. Alternatively, a trip can give people an emotional lift that lasts days.

A great deal of misunderstanding surrounds the phenomenon of ‘flashbacks’ after using LSD. Although these are poorly researched, there is no evidential basis for the myths that years after using LSD, people suddenly start tripping violently for no reason, causing all sorts of chaos like car crashes. However, in the days after a psychedelic experience, particularly after high doses, it may be surprisingly common, based on survey data, to get echoes of the trip experiences coming back, which may feel like momentarily tripping again. Such ‘flashbacks’ are usually not unpleasant or problematic. They are often brought on by alcohol or cannabis.

Much more rarely, long-lasting changes in perception called HPPD can happen (see below), this could be a seriously disabling condition at worst, unlike the brief flashbacks people get as an after-effect of tripping on LSD.

The first two decades following the discovery of LSD yielded intense research activities. These included LSD’s experimental use in psychotherapy, in the attempt to help with the treatment of a range of psychological problems and psychiatric illnesses. Although to modern eyes, some of this activity fell short of ethical and methodological standards, these years yielded some promising results.

Following the legislative control of LSD, clinical research ground to a halt, and regulatory and financial obstacles currently stand in the way of research on the therapeutic potential of LSD. Despite this, small steps have been taken in exploring the use of LSD in psychotherapy and in the treatment of cluster headaches, and there has been renewed interest in the use of LSD in the treatment of alcoholism.

It may be tempting for people to try to self-treat with LSD. Evidence that LSD can be an effective treatment with manageable risks only applies to the controlled procedures used in clinical studies, where professional psychotherapists help guide the patient’s experience. LSD alone (or any other psychedelic substance for that matter) is not the treatment because the idea is that LSD should be combined with professional psychotherapy. Without the appropriate safeguards, LSD may in fact worsen conditions like anxiety and other mental health issues.

LSD is less likely to cause physical harm to your life and health than many drugs with less fearsome reputations such as alcohol. However, the experience is often challenging and can be traumatic.

Risks of physical harm or death

Because it is so potent, the tiny dose used to trip on LSD is far below the quantity that would be toxic, so people do not fatally overdose on LSD. However, some other drugs with both hallucinogenic and stimulant (amphetamine-type) effects are sometimes sold as LSD or confused with LSD, and overdoses of these can cause unpleasant effects (e.g. trips lasting for much more than a day), or can cause harm or death. One such drug, DOB, can take 3 hours to kick in, potentially leading to overdoses if the user mistakes the effects for weak LSD and takes too much. It is important to be very cautious and suspicious of illegal drugs as the quality and authenticity of drugs is entirely unregulated. More recently, a newer group of highly potent phenethylamines (e.g. NBOMe analogues) have been detected on blotters and these might also be sold as LSD. In this case, details about their activity and toxicity are currently unclear.

Another risk of harm and death from LSD is the risk of accidents and injuries caused by odd behaviour and a lack of judgement. Common stories of people on LSD doing stupid things like blinding themselves by looking at the sun, or jumping out of high windows believing they can fly, are mostly mythological, but psychedelics do make people do strange things. People tripping on psychedelics are at risk of walking into roads for example, and a handful of suicides, suicide attempts, and self-injuries have been associated with the effects of LSD (though mostly in people with previous history of mental health problems).

Injuries and even deaths have resulted from encounters with police whilst tripping. On LSD you may lack the insight to understand and comply with police and therefore make yourself a victim of police violence and forcible restraint.

Risk of psychological or mental harm 

Rarely, people do have a prolonged and devastating bad trip, sometimes called a ‘psychedelic crisis’, and this can be very traumatic and even psychologically harmful. It may be impossible to entirely eliminate the risk of this happening, but certain factors make it more likely. If someone is going through a difficult time emotionally when they take psychedelics, if they are in an unfamiliar and chaotic setting with people that they do not know or trust, or if they take a very high dose, they are at far greater risk of having a bad experience.

As with any severe health problem caused by drugs, it is important to get medical help if you are with someone who seems to be undergoing a psychedelic crisis which you cannot relieve by supportive involvement. A trip cannot be turned off once it has started, and so sedation with benzodiazepines is usually used to lessen the traumatic effects and prevent the individual from hurting themselves or others.

People usually recover well from a psychedelic crisis when the drug wears off, or shortly thereafter. However, in very rare cases, psychotic episodes might persist even after the drug effects should have passed. The risk of this happening is negligible to people without a history of psychiatric problems, but people with pre-existing mental health problems or a predisposition to mental health problems (such as close relatives with anxiety, depression or schizophrenia) are thought to be at risk of lasting symptoms or relapses of existing conditions if they take psychedelics. The lack of sufficient evidence makes it difficult to quantify this risk.


HPPD or ‘Hallucinogen Persisting Perception Disorder’ is a very unusual and potentially harmful effect of LSD and other hallucinogens. HPPD is most often experienced as re-appearance of some of the effects experienced during the previously occurring hallucinogenic drug experience after some time without the drug. In most cases HPPD follows a traumatic hallucinogenic drug experience (‘bad trip’). In some cases, sufferers may feel detached from normality or the world.

HPPD was reported occasionally as longer-lasting, though complete or partial recovery usually occurs after weeks or months. Lingering HPPD has been reported more often following the use of LSD rather than other hallucinogens, higher doses and drug combinations. This kind of HPPD may occur in people with underlying psychiatric conditions or genetic vulnerabilities, but the evidence is very incomplete.

Mental health issues, such as anxiety and depression, even if never formally diagnosed, increase your chance of a bad experience or psychological harm. The chance of triggering psychotic episodes  is very low for most people, (especially when the user takes steps to contemplate and minimise the risks, see ‘set’ and ‘setting’ below) but higher for people who have, or have ever had a psychotic conditions such as schizophrenia, or their close relatives.

LSD should not be taken by those who are on psychiatric medications in order to exclude any potential for adverse drug interactions.

LSD is not considered an addictive drug. One factor that makes some drugs, like cocaine, addictive is that users (whether humans or rats) can find it difficult to stop using again and again to recapture the pleasurable features. Whilst LSD can produce intense joy, this cycle of compulsive re-use cannot occur because a dose that produced intense effects will do little or nothing if repeated in the following days. It takes a little while before the brain loses this resistance to psychedelic effects.

Furthermore, whilst lab animals eagerly take cocaine, few animals appear to self-administer LSD. However, some people are very attached to LSD, perhaps finding it an important spiritual tool, and take it frequently.

LSD has low risks to physical health, because it is not addictive and rarely used regularly. However, LSD has the potential to be an overwhelming and profound experience, and not always in a way the user might want. If people understand, as far as is possible, what LSD does, many will come to the conclusion that it is not for them.

Being cautious

Not all of the ‘LSD’ available is actually real LSD, and even the dealer may not know this. LSD has a nearly unique property; exceptionally low toxicity. That means that taking far too much might be incredibly distressing (you might even need medical help), but it will probably not harm your body. However, if the ‘LSD’ is actually another drug like an ‘NBOMe’ chemical, taking much too much could kill you. The trade in LSD is illegal, which makes it especially hard to be entirely sure that the drug is just what it is supposed to be. This risk is particularly high if you intend to take an unusually large dose from a supply you have not used before.

Being prepared

It is difficult to measure doses of LSD reliably as they are very inconsistent, and impossible to fully imagine the effects if you have not tried it before. Therefore, LSD should be avoided if the user is not prepared to have a more overwhelming experience than they might ideally have intended. Many people choose not to take psychedelics because they do not want to feel out of control.

The effects that psychedelics have are normally only controllable to some extent but proper planning is advisable. Whilst many people think that the use of powerful and controlled drugs can never be considered entirely responsible and well-judged, people who are informed about the factors which affect the mood of a trip are certainly less likely to experience unpleasant thoughts and effects.

Set and setting

A useful way of remembering the factors that help determine whether a trip is rewarding or nightmarish is the concept of ‘set’ and ‘setting’.  A person’s ‘set’ (or mind-set) includes their mood, disposition, thoughts and expectations. A person’s ‘setting’, is the specific place and social situation in which they take the drug. If an anxious and miserable person accepts LSD without having planned for this at a chaotic party where they know and trust no-one, then their trip may be a disaster. Taking hallucinogens in a calm, familiar place, with someone you trust to be your sober ‘trip-sitter’ is far less likely to be something regretted for life.

Having a sitter

Psychedelic drugs trigger a complex range of altered states of consciousness which can make people highly suggestible, especially in the presence of other people. This also means that their ideas strongly influence the way that they perceive the world. For example, once the thought has occurred that they might be dying, they may see their skin appearing to go grey and blotchy. However, this suggestibility is not necessarily all bad; it means that a sober helper, (sometimes called a ‘trip sitter’) can often successfully reassure them, or distract them with a change of scene or showing them something. It is essential to remind someone who is showing signs of beginning to have problems that what they are feeling is not real, and that they have taken a drug which will wear off. Reassuring comments and gestures can be helpful.  Have a discussion before you begin as to what to do if things do not go smoothly.

LSD is probably one of the most mythologized and demonised drugs, and its history is full of episodes which are as outlandish as the stories, such as the illegal experiments with the drug carried out by American and British intelligence agencies. Countless urban myths exist about bizarre and frightening things people did whilst tripping.

“Bad Acid”

People have believed in batches of so-called “bad acid” which are blamed for horrible effects and bad trips. Doses of different batches can be very variable and ‘bad’ experiences with LSD can usually be related to unwanted high doses, irresponsibility or unpreparedness and/or the ingestion of a different substance. There are no different types of LSD.

LSD stays in your spinal fluid, causing flashbacks years later

LSD does not stay in your body for long. Flashbacks and HPPD are poorly understood, but the symptoms occur in the absence of LSD.

Orange Juice/ Vitamin C can be used as an antidote to stop a bad trip

This is not true, there are no easy home remedies to end a trip, although doctors use benzodiazepines to ease agitation. However, people are very suggestible when tripping and this can contribute to the perception of such effects.

You can be declared legally insane if you take LSD more than seven times

There is an old rumour that taking LSD more than seven times means that you can be declared legally insane. This is not true and there are plenty of people who have taken LSD more than seven times and are not insane.

People going blind staring at the sun

The rumour about people going blind from taking LSD and staring at the sun was created by a TV show in the 1960s. However, there have been a few case reports of people partially damaging their eyes from staring at the sun whilst on LSD. People do strange things whilst on LSD and LSD dilates your pupils which exposes your eyes to more light than usual.

People think they can fly and jump out of a window

People have fallen out of windows and off cliffs whilst on LSD, but these were probably accidents due to impaired judgement, or suicides, rather than thinking they could fly.

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Khat is a bitter-tasting plant with stimulant effects. It is chewed mostly by people of East African descent. Occasional use has very low risks, but like all drugs it can cause harm, especially when it is used several times a week.

Khat contains stimulant drugs called cathinone and cathine in its leaves and stems. It is possible that other substances in khat leaves also contribute to its  effects and its harms. The cathinone begins to break down after picking, so khat users try to get it fresh for maximum effects. Khat has been available in Europe for many years now, but it is still rarely used by people who do not come from a culture where it is traditional.

Fresh khat looks like hedge trimmings. It is often sold in small bundles wrapped in a banana leaf. It is bought and consumed in places called ‘mafrishes’, and is also sold in some shops. Men may chew it socially in the mafrish, or they take it home. Women are more likely to use in the home only. The bitter leaves are picked off, crushed by the teeth and held in the cheek over an hour or so. In countries where khat is illegal it may instead be dealt secretly like other illegal drugs.

Dry khat leaves are available in some countries. Depending on how they are dried, these can contain much reduced levels of cathinone compared to fresh leaves, and so will probably be less potent.Whilst the tradition of chewing khat leaf has relatively low risks compared to other drugs, risks could be higher with any other form of khat product made to extract or concentrate the drug chemicals. Such a preparation could also be illegal even where khat is legal.

Khat contains cathinone, a stimulant drug closely related to mephedrone and amphetamines. As time passes after picking, the amount of cathinone in the leaf falls as it is coverted to a weaker but similar drug chemical called cathine. Cathinone increases the concentration of dopamine in the brain. Dopamine is a chemical messenger involved in motivating us to do things that feel ‘rewarding’, so this is why taking khat persistently can be addictive to some people. Cathinone also has effects on noradrenalin and serotonin, genrally boosting these too. Noradrenalin is similar to adrenalin, and is involved in the jittery, alert feeling that stimulants produce, as well as the physical effects on blood-pressure, heart rate and energy. Serotonin is involved in mood, so is linked to the happy feeling khat can give.

When the drug wears off, it may take a little while for the brain to rebalance the levels of chemicals that khat has interfered with, which may lead to a ‘comedown’, with approximately the opposite effect of the high. If khat makes a person feel energetic, happy and motivated, they may feel tired, irritable and demotivated afterwards.

Khat gives a feeling of wellbeing and alertness, which may encourage enthusiastic chattiness for a few hours. It can reduce appetite. After the high has gone people can get mood swings, and feel grumpy and irritable. Khat often makes people constipated, and will prevent you sleeping if you have it in the hours before going to bed.

There are no known evidence-based medical uses of khat. However, in the tradtional North-East African cultures where it is popular, it has been used as a medicine to treat depression, gastric ulcers, hunger, obesity, and tiredness.

The risks of khat from experimental or occasional use are low. Reducing the risks of khat is mostly a matter of keeping use to a moderate level or avoiding the drug. Children are likely to be a much greater risk, and therefore khat should not be available to children. It is sensible for pregnant women to avoid it too, because it is linked to lower birthweights. Babies with lower birthweights are more likely to suffer from a broad range of medical problems.

The slow process of chewing khat in the plant form means that the effects come on gently compared to taking something like amphetamine powder, making this a much less risky drug for healthy people. It increases heart-rate, blood-pressure and may make people feel hot, so if the effects are uncomfortable it is best to stop use.

Using khat on a daily or near daily basis can be harmful and has even been associated with deaths(see below).

In countries where khat possession is illegal, users risk persecution, arrest and a criminal record. There have also been cases of people being duped into carrying khat into a country where it is not permitted, resulting in them being convicted of serious drug-smuggling crime they were not aware of committing.

Because of its effects on the heart and blood-pressure, khat is probably riskier for anyone with high blood pressure or heart problems. The added strain could make heart-attacks more likely.

Because of its amphetamine-like mental effects, and the low moods that can occur after the high, khat is riskier to those with mental health problems. Even if you have not suffered mental illness, but are going through a bad time or otherwise do not feel stable and well, it may be a good idea to avoid khat. Some people in the Somali community in Europe suffer symptoms of post-traumatic stress disorder (PTSD) following their experiences of war in Somalia. It is thought that khat is responsible for worsening PTSD and contributing to breakdowns and even psychotic episodes in sufferers.

Khat (presumably long-term excessive use) can cause liver damage, that can be catastrophic, and even fatal. Anyone with existing liver problems could be at greater risk.

Khat is very often combined with tobacco smoking. It is possible that sessions of khat chewing result in smoking more, increasing the chance of the severe harms that smoking causes.

When this stimulant is combined with alcohol, which causes disinhibition, there are credible concerns that the likelihood of drunken violence or risky sexual behaviour might be raised. There is minimal scientific evidence for this. Both alcohol and khat can injure the liver, so in combination the harms could be compounded.

Combining khat with other stimulants like coffee could increase the chance of unpleasant jitteriness or heart palpitations.

Although this is not recorded in the scientific literature, khat could also potentially increase the risk of serious harm like overheating or heart attacks after taking strong stimulants like cocaine and amphetamine.

You should tell your doctor if you are a regular khat user as this could intereact with drugs you may be prescribed. For example, you should not be prescribed MAOI antidepressants, which could prevent your body breaking down the khat drug chemicals causing serious overdose effects.

Khat seems to be addictive to some, but is towards the bottom of the scale in terms of the severity of addiction. The people who suffer harm from khat are almost exclusively very heavy users, who may be addicted to some degree. However, the vast majority of khat users are not driven to use by any addiction.

If using khat is becoming a priority in your life, this is a problem that needs addressing. Firstly, the risks of khat to body and mind are more likely if you use it excessively, and secondly, when drug use becomes a major focus of your days, employment and family can suffer. If you find it hard to limit your use, your doctor could offer advice and assistance.

The topic is controversial, but it seems that physical addiction to khat is closer to addiction to coffeein terms of severity than adiction to amphetamines, leading to some unpleasant but not severe withdrawal symptoms.

Khat does not give the rewarding rush which makes cocaine and other strong stimulants addictive, so unlike those drugs it is very unlikely to ‘hook’ new users after a few doses. However, fresh khat is flown to Europe several times a week, which allows people to develop a daily habit. After persistent use, damaging addictions can develop, especially as it is tempting to avoid the low mood and irritability that often follows a khat high by just chewing more.

Addiction is never a risk that applies equally to all users. Other factors in the lives of users act as gateways to persistent use and then addiction. For example, khat can become overused when it is used as a way of coping with flashbacks to war experiences (PTSD) or coping with other stressors. Unemployment can provide the empty time needed for persistent chewing. Therefore addiction, and khat’s other harms are as much a result of and a contributor to the problems in the lives of users than a cause of the problems.

People addicted to khat can suffer constipation and related gastric problems, and people may not eat properly as khat lowers appetite. The social and economic effects of khat addiction may be more significant, with the possibility that khat chewing could become a barrier to employment. In countries where it is illegal, maintaining an addiction may force users into leading a hidden life, dealing with a criminal network.

Khat withdrawal is relatively mild. Low moods, irritability and cravings can be difficult to deal with.Weird nightmares can occur. There may be physical symptoms like slight trembling.

Long-term khat use can cause severe injury to the liver, which can result in death, or the need for liver transplantation. There is no published evidence yet which determines the level of use necessary to cause these very serious effects. In one case where a transplant was needed, it was noted that the patient and his family had not realised that khat was a drug and could possibly be the cause, allowing his health to deteriorate for three more months until the probable cause was discovered.

The drug chemicals in khat are similar in action to chemicals like amphetamines that can have severe psychiatric consequences. However, the chemicals in khat are very slowly released by chewing leaves, which reduces the risk of all harms. Persistent use of khat has been linked to mental health problems, both mild and serious, but there is disagreement over whether the risk is large and indiscriminate, or small and avoidable.

It seems that people who use the drug on a daily basis may become short-tempered. Khat, like most mind-altering substances, can be destabilising to people with pre-existing mental health issues, and such problems are also likely to contribute to using khat too much, for example as an escape from PTSD symptoms. Taking stimulants excessively, especially when normal patterns of sleeping and eating are disrupted, can lead to a breakdown of mental health.

Unless you have underlying health problems, using khat in moderation has a relatively low risk of harm. Khat use is not entirely safe, and most users could improve their health and wellbeing, or reduce the risks of harm, by using less or quitting entirely.

If you do wish to use khat despite the risks, try to avoid chewing one bunch after another and avoid using two days in a row to keep the risks down. If you miss out on eating and sleeping because of khat you may become more vulnerable to mental health problems. Try to wash khat, it is conceivable that pesticide contamination could be responsible for some harm.

Consider your reasons for using khat. If you are taking khat for a particular purpose, for example to escape thinking about your problems, to kill time, to alleviate feelings of depression, or to work without sleep, you could find yourself becoming dangerously reliant on it. If you can take it or leave it, but enjoy it socially once in a while, you probably have a healthier relationship with it.

Excessive use could cause very serious harm or even death. If you use khat regularly and have health problems, consider the possibilty that khat could be involved and remember to tell your doctor that you use it.

The harms of khat, like those of many other drugs, are often overstated in the media.Within cultures which use khat, it may be considered to be a special food rather than a ‘drug’, much like coffee and beer are often seen as drinks, not drugs, by their users. This can cause harmful miscommunication with doctors who may ask khat users whether they take any ‘drugs’ and be told “no”.

There are risks of dangerous misunderstandings regarding legal status, which differs from country to country. There have been cases of people being persuaded to carry a suitcase of khat into another country. The courier may believe or be told that this is a legal way to make some money, and then be prosecuted for drug trafficking.

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Ketamine (ketamine hydrochloride) is an anaesthetic and analgesic (pain killer). Ketamine was developed in the 1960s for medical use and is now used widely throughout the world for anaesthesia and pain relief in both humans and animals. It wasn’t long after its invention that it began to be used as a recreational drug with dissociative and psychedelic properties.

Ketamine is a white/transparent when pure, and often sold as a powder of tiny crystals. It is often crushed into a fine powder so it can be snorted up the nose. Occasionally the powder can be other colours, such as off-white or brown.

Ketamine also sometimes comes in pills. These could contain other drugs, which increases the risk of a bad reaction. It has even been sold as or confused with ecstasy pills.

Some people get ketamine in liquid form (or dissolve it) and inject it for a faster, stronger effect. Injecting drugs is more dangerous for many reasons. For example, it is easier to take too much and can cause injuries and infections such as HIV (sharing needles).

Ketamine is a dissociative anaesthetic. When used medically, it is given in high doses that blocks pain signals and makes people unconscious. The lower doses used recreationally produce very different effects, sometimes including hallucinations, which are not well understood. There are similarities between the strange states of mind caused temporarily by ketamine and the experiences of people suffering from schizophrenia.

Ketamine is an essential medical and veterinary drug used for anaesthesia and pain relief under a wide range of circumstances. Ketamine is much less likely than other anaesthetics to depress the heart and respiration, so it is the anaesthetic agent of choice in low income countries and in environmental/conflict disasters where there are few trained medical personnel, anaesthetic machines or consistent sources of electricity. In the western world ketamine is the most commonly used veterinary anaesthetic, particularly in horses and the more unusual species. In developed countries ketamine is less commonly used for routine anaesthesia in people as it may cause hallucinations during recovery; more conventional anaesthetics are preferred where trained anaesthetists and appropriate equipment are readily available to monitor the patient and support respiration.

Ketamine is a potent pain killer and is particularly useful for children undergoing agonizing procedures such as treatment of burns. It is now also an important treatment for chronic pain.

New therapeutic uses for ketamine have more recently been identified, including treatment of depression and refractory status epilepticus. A single low dose of ketamine can rapidly lift depression, although the effect does not last long-term. It is thought to work by causing new connections (synapses) to be made in the brain. This is a promising lead for the development of new treatments because conventional antidepressants take some time to work. Self-treating using ketamine puts the user at risk of the harmful effects of ketamine, and it has not yet been established through large-scale trials that the benefits outweigh the risks.

Ketamine produces very different effects depending on whether someone takes a little or a lot. It is a strong drug and it is easy to take more than intended. It is therefore better for inexperienced users to start with a small dose first before they consider trying to get the effects of a larger dose.

Low to moderate doses

Ketamine can give sensations of lightness (like walking on the moon), dizziness, and euphoria. It makes people’s thoughts flow randomly; ideas can seem special and important, or pleasantly or unpleasantly muddled. Things may begin to look and sound different or somehow unreal. There is always a higher risk of accidents whilst using ketamine. Taking any depressant drug, such as alcohol, can very easily and quickly make the effects much stronger and riskier.

Higher doses

The more ketamine that is taken, the harder it is to stand up and move about. Quite large quantities lead to exceptionally odd feelings such as separation between the mind and the physical body, which some find pleasurable and others find distressing. Unpleasant side-effects like nausea and vomiting can occur. Ketamine can produce delusional thoughts much like those associated with schizophrenia. Very large quantities lead to users losing touch with their identity and surroundings altogether, which is called k-holing. People k-holing may be unresponsive, although inside their mind they may be experiencing vivid hallucinations. Users can have notions and hallucinations which can feel very real, and can be anything from wonderful conversations with angels, to being convinced they are dying. The risks of accidents, overdoses and anxiety described below are increasingly significant at higher doses.

People can die after taking ketamine. People who die or end up in hospital almost always have combined ketamine with other drugs, particularly alcohol. Taking ketamine with stimulants (such as cocaine and ecstasy) may overload your heart. Taking it with depressants (such as alcohol, GBL or heroin) may make you become unconscious quickly and unexpectedly, and can stop your breathing or allow you suffocate on your own vomit.

Ketamine works in several ways to make you particularly vulnerable to accidental injury and death; even smaller amounts will decrease your ability to make sensible decisions or recognize dangers (like roads). Larger amounts have anaesthetic effects; people have died by lying outside on a cold night without awareness of the cold, and by falling unconscious in the bath and drowning.

Tripping on ketamine can be an utterly overwhelming experience, especially if the user does not expect its powerful effects. Users can freak out whilst taking it and sometimes end up being rushed to hospital. Such anxiety attacks produce a dangerously racing heart and palpitations as well as extreme agitation. This can be a seriously traumatic experience, even if it doesn’t cause physical harm.

People with schizophrenia, or who have ever suffered a psychotic episode, should avoid ketamine. The drug has been demonstrated to bring back symptoms of psychosis, and these could persist beyond the period when the drug is in the body.

Drugs which radically affect consciousness are more likely to cause panic and fear in people who suffer anxiety, whether this has been diagnosed as a disorder or not.

Ketamine increases heart-rate and blood pressure. These effects are usually quite minor, but could be dangerous for people with related health problems or who combine it with other drugs.

When people die after taking ketamine, they have usually combined it with another substance.

Taking with depressants (such as alcohol, GBL , benzodiazepines such as valium, or opiates such as heroin) may make you become unconscious quickly and unexpectedly, and can stop your breathing or allow you suffocate on your own vomit.

Taking ketamine with stimulants (such as cocaine and ecstasy) may overload your heart. The chance of agitation and anxiety is also increased. Stimulants may keep you moving when the effects of ketamine would otherwise have immobilised you, increasing the chance of accidental injury.

Whilst many people use ketamine on occasion without feeling cravings, some people get addicted to ketamine use and may use it daily. People can struggle and fail to be able to stop using ketamine. Tolerance builds up, so users need much more ketamine to get the effects they like. Signs of tolerance should be considered an early warning sign of addiction and harmful use.

People addicted to ketamine can suffer strong cravings, anxiety and misery, and even shaking and sweating when they try to go without. Such withdrawal symptoms are not dangerous and eventually pass.

Addictive regular use of ketamine can cause serious mental and physical harm.

Mental impairment

Taking ketamine regularly seems to affect the mind, particularly memory.  The effects are not serious enough to count as a mental disorder, but regular users may feel that they’re not nearly as sharp as they should be. This could be very bad for work, education and relationships. These harmful effects seem to fade when people give up the drug.

Urinary system damage

People who use ketamine more than a couple of times a week are at high risk of damaging their kidneys and especially their bladder. Once the damage is done, the organs do not always recover. The bladder condition, called ketamine-induced ulcerative cystitis, starts with the need to urinate very often, and leads to painful urination. Sufferers may be prone to wetting themselves and can  have blood in their urine. A few young people have had to have their damaged bladder removed, which leaves men unable to get a natural erection and both genders unable to urinate naturally for life. This disease can even encourage more ketamine use, or prevent users quitting, as ketamine temporarily eases the pain.

Ketamine cramps

Regular users get severe abdominal pain often called k-cramps. Their cause is unknown but they seem distinct from the bladder damage.

There are always risks to using ketamine. However, if you do take drugs, you can make simple choices to improve the chances of a good experience, rather than a regretted, harmful or even fatal one. Here are some things to consider.

How much are you taking and how often?

Taking bigger amounts, and taking it frequently, means higher risks. The most severe harms, including permanent bladder damage, affect people who take ketamine regularly.

First time users should be especially cautious with dose. Some users plan and measure out how much they intend to take, and only have that amount accessible. Otherwise, it can be tempting to keep taking more whilst you are less capable of making sensible decisions.  It’s important to keep track of whether you or your friends are taking increasingly large amounts, or using ketamine increasingly often, as this can be a sign of an addiction developing.

Are you taking anything else?  Mixing drugs is much riskier. 

Drug effects are unpredictable, but mixing drugs makes the effects on your body and mind even harder to control. Deaths after ketamine use usually involve mixing it with other drugs. Ketamine plus a sedating drug like alcohol can stop you breathing.

How appropriate is your setting and state of mind? 

If you are anxious, or feeling down, the drug may exaggerate these feelings and give you a terrible experience. Additionally if you are in a stressful, unfamiliar environment with strangers, the risk of having a bad time, or experiencing physical harm, is increased.

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Heroin is the commonly used name for the drug diacetylmorphine (diamorphine). It is a semi-synthetic opiate drug, made by chemically altering morphine, which comes from opium poppies.

All heroin can cause serious harm, but many of the harms from the use of heroin depend on the type and quality, how the user gets it in into their body, and what else is getting in too. The way it is used also affects the chances of getting addicted.

Illicit ‘heroin’ is typically less than 50% pure. The other constituents may include chemicals left over from the manufacturing process, chemicals added to enhance or mimic the effect (other opioids or sedative drugs), and stuff to bulk it up, like paracetamol. Heroin powder may also contain materials that give rise to infections, such as materials that contain spores of the bacteria that lead to anthrax or clostridium infections.

With the variation in purity, the ‘strength’ of any given powder can be hard to know. At times this may lead to overdose when particularly high purity batches are sold on the illicit market.

Brown heroin

Brown powder heroin is the main type of heroin found in Europe. It is an off-white to brown powder or powdery clumps that consists of heroin ‘base’, plus various other potentially harmful substances (see below). Base heroin becomes a vapour when heated and it is often ‘smoked’ (‘chased’) from foil. It can also be snorted although this method of use is uncommon. Base heroin does not dissolve in water so to inject it users need to use an acid (like citric acid) to convert it into the ‘salt’ form.

Heroin hydrochloride

Unusual in Europe, this is the hydrochloride salt form. It dissolves in water and therefore easily prepares for injection. It can also be snorted, but is less suitable for smoking as it does not vapourise easily. Pharmaceutical heroin, diamorphine hydrochloride, is a white odourless powder.

Black tar heroin

Common in the USA, black tar heroin is rarely found in Europe. It is made using a cruder technique, which results in it consisting mainly of drugs that are part-way between heroin and morphine (3-MAM and 6- MAM). It resembles tar- being black or very dark brown, ranging from gooey to crumbly. It can be smoked and injected, though it is considered particularly damaging to inject.

Injecting- (usually into a vein, sometimes under skin or into muscle)

As with the injection of any illicit drugs, injecting heroin poses the greatest risks. These include bacterial, fungal and viral infections, including abscesses at the site of injection, the collapse of veins, and infection with hepatitis HIV and other pathogens.

Injecting, particularly intravenously, results in a strong and addictive rush of euphoria. If someone has regularly injected heroin into their veins, it tends to be very difficult to go back to using one of the less intense methods. Injecting heroin under the skin (subcutaneously) or into muscle (intramuscularly) is possible but gives a less of a ‘rush’. Subcutaneous and intramuscular injections pose a higher risk of bacterial infection at the site of infection.

‘Smoking’ (the drug is actually vaporised rather than burned to produce smoke)

Compared to injecting, there is very much lower risk of overdose when smoking heroin- users have better control over their intake and can feel the effects of the drug very rapidly, regulating or stopping intake as necessary.

Rectally- ‘plugging’ it (squirting it up the rectum with a syringe)

Rectal use avoids injecting harms but has in common with injecting the fact that there is not much you can do if you use too much, which may be a seemingly small amount. Snorting avoids injecting harms, but most European heroin is not ideal for snorting.

Heroin is used recreationally because it produces intense feelings of euphoria and relaxation. Dependent individuals use it to ‘feel normal’ and avoid withdrawal symptoms. It works by affecting brain receptors involved in reward, pleasure and the perception of pain. The chemical modification of the morphine molecule to produce diamorphine has produced a drug that crosses the blood-brain barrier more quickly than morphine- this produces a rapid rise in brain levels of the drug and what users term a ‘rush’.

Heroin is a strong sedative and makes users feel peaceful, cosy and relaxed. Taken in a way that puts it into the bloodstream quickly (injecting mainly, but to a letter extent snorting, smoking, plugging), it will give a ‘rush’ of euphoric pleasure.

Some people experience vomiting and nausea, especially the first few times they use heroin, which introduces a risk of death from choking on inhaled vomit. Heroin also causes significant constipation.

Physical dependence will result after  regular, repeated use. Physical dependence means that the person using will experience withdrawal symptoms if they do not take heroin.

Diamorphine (pharmaceutical heroin) is used medically in many countries. Its primary use is for relief from severe pain. It is used for acute pain, (for example for heart attacks and accidents involving serious injuries) and chronic pain, for example that resulting from terminal cancer.

In some European countries, people with heroin dependencies are given pharmaceutical heroin in specialist clinics where they can inject under supervision. This reduces the harms of using street heroin, and has been shown to prevent almost all overdose deaths, however it remains controversial.


Heroin and other opioids cause respiratory depression when used in overdose. This is when the drugs act on the brain and reduce the natural drive of the body to breathe.

Additionally, people can die from becoming unconscious and choking on their vomit. These risks are made greater if heroin is taken with other drugs that cause sedation or make you vomit, such as alcohol.

Overdoses can be caused either by accidentally taking too much, or by taking the same quantity of a purer batch of heroin, which amounts to the same thing. If heroin is injected, overdosing is much easier.

Furthermore, many users have overdosed on an amount of heroin that they have taken many times before. This can happen because of a drop in tolerance. Tolerance  will reduce in a matter of days without heroin and its relatives, or only weak heroin, meaning a previously normal amount could cause overdose. Overdoses are very common when heroin users come out of prison due to little or no tolerance, or users bingeing on freely available drug supplies.

Additionally some tolerance is dependent on the setting and routine in which a person normally takes heroin. Cues such as a particular room, handling injecting equipment or even a smell, will trigger changes in the body in preparation of the drug. This may explain some cases when heroin users have overdosed when taking the usual amount in a new or different environment.

If an overdose is suspected immediate medical attention is required. Symptoms include slow, irregular or shallow breathing, pinpoint pupils, weak pulse, bluish lips and nails, muscle spasms.  A drug called naloxone is the emergency treatment for overdose. There are many urban legends for reviving someone in an overdose situation, but medical treatment with naloxone is the only appropriate course of action in the case of an overdose- failure can act appropriately can result in an avoidable death.

Using illicit heroin long term, and the lifestyle that can accompany it are likely to lead to physical health problems.  Aging drug users have increasing vulnerability to overdose. Overdoses cannot always be seen as just a one-off accident.

The chance of your breathing and heart being dangerously affected by heroin will be increased if you have a heart or breathing condition, or low blood-pressure. Neurological or muscular conditions that could result in breathing being weakened might also increase risks.

Some people are allergic to opiates like heroin, and others can suffer serious allergic reactions to various substances that heroin has been cut with. Life-threatening asthma attacks have been caused by smoking or snorting heroin.

Injecting heroin can spread diseases and also makes wounds that often become infected. Any condition that lowers the immune system will increase the risks.

Many overdoses and fatalities result from the combination of heroin with other drugs. Other sedatives such as alcohol, benzodiazepines (e.g. diazepam- ‘Valium’, and temazepam) and other opiates (e.g. methadone) are frequently involved in accidental overdoses.

Combining heroin with a stimulant could also raise the risk of harm or death, although the evidence is not fully clear. The combination of heroin and cocaine, often called a ‘snowball’ or ‘speedball’, is a well-known example. This seems to be linked to a greater chance of overdose , although there is some evidence that it simultaneously may decrease the chance of that overdose being fatal.

Heroin can be very addictive. There are various aspects to heroin addiction. Firstly people may keep taking the drug because it is very pleasurable. After taking the drug repeatedly tolerance may then develop. Part of the way the brain and body develops tolerance is by producing the opposite effect of the drug, which means that a tolerant person will need the drug to stay at normal levels. Without the drug the person will experience withdrawal effects. Withdrawal effects are in some ways opposite to the effect of the drug. For example, heroin causes constipation, so a person can experience quite extreme diarrhoea in withdrawal.

Many people who become addicted to heroin suffered trauma and/or problems with mental health in their early life, before using heroin. This suggests that some people use it despite the risks as a form of self-medication, which is likely to lead to dependence.

Withdrawal symptoms include: sweating, depression, stomach cramps, diarrhoea, feelings of discomfort and unease, nausea and vomiting, and craving for heroin. Heroin withdrawal is very unpleasant which is a major reason why people addicted to heroin continue to use despite experiencing more and more harms, and less pleasure from use as time goes on.

Heroin’s illegality, its addictiveness and its disruptive influence on employment means that some users can be drawn into making money in ways they otherwise wouldn’t, such as stealing or prostitution, to maintain a heroin addiction. Many heroin dealers are users who sell drugs to fund their own habit. The needs of dependents, such as children of heroin addicts, are often compromised by the time and money needed to  maintain a heroin addiction.

There is also still a significant social stigma over heroin use. People who are dependent on  or have previously been dependent upon heroin may find it hard to be trusted and  employers may discriminate against them.

Injecting heroin carries the risk of infection from viruses or bacteria, especially if people are sharing needles. Repeated injections cause veins to become scarred and collapse.

The harms of heroin are linked to the harms of poverty and unstable lifestyle. Many problems may be caused by neglecting other things necessary for wellbeing in order to maintain the habit.

Street heroin is a drug which always has a high potential for causing harm. However, there is enormous variability in the risks suffered by different users with different habits. When the costs of use can be so high, there is an especially strong reason to make every effort to minimise harms.

Avoiding use, minimising use, avoiding addiction.

Whilst the body does not immediately develop a physical dependency, people will often like the drug and want to repeat the experience from the first use. If you encounter heroin regularly in your social or family life, this constant availability will add to the temptation to repeat an initial experience, as will stresses in life.

If you do use heroin occasionally and do not wish to stop despite the risks, it is important to be vigilant and reactive to signs of dependence. Growing tolerance for heroin (needing more to feel the same effects) is an important warning sign of some of the changes in your brain chemistry that lead to cravings and withdrawal effects when you don’t use.

How are you taking it?

Injecting heroin carries with it more risks than smoking or snorting heroin. Firstly, with heroin injection the total dose is taken in one go, so it is easy to overdose. Judging the amount to use is made more difficult because heroin purity varies. It is therefore much better to take a small amount to see how strong it is before taking a moderate dose. As injecting heroin produces such a big rush it is easier to become addicted to heroin when injecting.

If a user is injecting, they can still do many things to reduce unnecessary harms. Deliberately, or accidentally sharing used needles carry the risk of infection from viruses such as HIV and hepatitis. Using new sterile equipment reduces the risk of  infection. Using lemon juice or vinegar as acids to make brown base heroin is very risky – lemon juice is linked to fungal infections including inside the eyeball. In many countries, advice on safer injection and free equipment can be accessed at needle exchanges.

Are you having anything else? Mixing other drugs with drink can be very risky

Taking heroin with any other drug that can stop breathing (e.g. alcohol or benzodiazepines) increases the risk of overdose. Additionally, taking heroin with stimulants like cocaine and speed (amphetamine) can suppress some of their negative side effects . This is a problem as the effects of cocaine or speed will wear off before heroin does meaning a person could take both drugs and then overdose when the stimulant wears off. Doing this may also be more addictive.

Can heroin dependence happen from one use?

It takes repeated uses over a short space of time to become physically addicted to heroin, so that symptoms appear when you don’t take it. However, heroin is, at least to some people, immediately satisfying and pleasurable (even if it causes vomiting), and some dependent users feel that they ‘fell in love’ with the drug from the first try. Heroin can give a deep feeling of relief and comfort, and having had it once, any time when an individual feels in need of relief and comfort, the temptation to use it may arise.

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Gamma-hydroxybutyric acid (GHB) is found naturally in tiny quantities in the human body and other animals. The GHB that is available as a recreational drug or medication is manufactured but is still the same compound.


Gamma-butyrolactone (GBL) is a GHB ‘prodrug’. This means that it is converted into GHB in the body, so it has very similar effects and harms.
1,4-BD (1,4-butanediol) is another GHB prodrug, however, it is much rarer. It is likely to share the effects and harms of GHB.

They are all central nervous system depressant drugs.

GHB is usually identified as a colourless, oily liquid but it is also encountered as a whitish powder. It is odourless and has a salty/soapy taste.

GBL is a colourless, oily liquid that has a strong chemical smell and taste.

GBL is used as a solvent for cleaning metal, paint stripping and glue removal.

GHB and GBL are usually ingested orally by using a pipette or syringe to transfer a small amount of the liquid into another drink.
Rarely, some people may inject GBL, but this is very dangerous.

Some people may also snort GHB when it is in powder form. Again, this is rare and may make it harder to monitor dosage.

GHB works in the body in two ways to produce its effects.

– Activates inhibitory GHB receptors in the brain, producing sedative effects and stimulating the release of dopamine and growth hormone.

– Activates GABAB receptors in the brain, producing sedative effects.

Much like alcohol, these drugs are intoxicating nervous system depressants and are often used in a social context where they can make people happy and confident. People under their influence can be chatty, outgoing, and giggly, although some others become withdrawn. Like alcohol, it may make people say and do things they normally wouldn’t (reduces inhibitions). Some users find that for them, the drugs enhance sexual feelings. After a bit of GBL or GHB people start to lose the ability to concentrate and think straight.

As with alcohol, the depressant and euphoric effects become clearer at high doses. GBL and GHB are much more potent than alcohol however, meaning that only a small amount, one swig too many, can be enough to accidentally cross the line between joy and coma. Unpleasant effects like vomiting and confusion become more common as the dose, and risks of harm rise. Technically, GHB and GBL have a ‘steep dose-response curve’ which means that a second or third dose may have a much greater (and unexpected) effect than the first.

People can become dependent on GHB, GBL or 1,4 BD, so sometimes it is used more to relieve a craving, stop withdrawal symptoms or feel normal rather than to have fun. Some users find sleep is impossible without the drug. As with alcohol, GHB, and GBL are sometimes used as a way of dealing with problems or depression through the obliteration of all feeling.

Some people report feeling groggy or fuzzy-headed as an after-effect of the use of GBL or GHB. However, the after-effects are generally reported as milder than the after-effects (hangover) from an amount of alcohol that causes a comparable intoxication. This should not necessarily be seen as an advantage as easier recovery may be one of the aspects that allow some people to quickly become heavy users and addicts.

GHB has two main medical uses.

Xyrem, which consists of the sodium salt of GHB (sodium oxybate), is prescribed to treat excessive daytime sleepiness and cataplexy (sudden temporary muscle weakness), which are symptoms of narcolepsy.

GHB is sometimes used to aid alcohol withdrawal, opioid withdrawal, treating fibromyalgia, essential tremor, ME, and other conditions. However, there is not yet enough scientific evidence to support its use in this way.

Using GHB or GBL to self-medicate for any health issue puts you at risk of all the harm these drugs can cause, especially addiction. It is likely that these risks outweigh any potential benefits.

There is a particularly high chance of overdose with GHB and GBL. This is because there is a very small difference between an enjoyable dose and a dangerous one. The steep dose response curve of the drugs also means that similar doses can be much more powerful on redosing. Overdose can lead to unconsciousness, depression of breathing, and brain damage. It is important to seek medical assistance as soon as possible if an overdose is suspected.

The drugs may take longer to take effect than expected, and factors like stomach contents can make this time vary. This means someone who takes a second dose without having waited for the effects to reach their peak could be taking a big risk. GBL is also much more potent than GHB, so a smaller dose is required. To reduce risk of overdose, users should only take smaller doses after their first dose, having given enough time to feel the effects reach their peak.

Sometimes, these drugs are purchased as a solution already diluted by some amount, other times they are pure. Pure GBL sold for industrial use is often prepared into a solution of known strength by the user by transferring a set amount of GBL into a set amount of water or juice, for example. Knowing the strength helps with getting the dose right. Weaker solutions of these drugs are less likely to cause accidental overdose. The drugs, when consumed pure or almost pure, can taste very unpleasant or burn.

There is a danger of users losing track of drinks or bottles containing these drugs, leading someone to take an unintended overdose. Therefore, it is important to closely monitor any drinks containing GHB or GBL.

These drugs are not known for being adulterated with other harmful substances, but this is always a risk. Even products sold as commercially available solvents may contain harmful impurities.

Any amount of GHB or GBL decreases a person’s ability to make sensible decisions. The drugs also reduce coordination, making simple tasks much more difficult. Care should be taken when crossing roads, for example, as it may be more difficult to judge distances of passing cars. Of course, driving after taking the drug would be particularly dangerous.

Users can become confused, and less able to react appropriately to what is happening around them. Some become aggressive, which can pose a problem in hospital emergency units if a person is agitated and difficult to manage.

GHB has been used as a tool to carry out sexual assaults. Though the moral responsibility is wholly with the assaulter and not the victim, everyone can reduce the risks of becoming a victim by not leaving drinks unattended, not accepting open drinks, and by reducing their drinking/use of other intoxicants. Also, you should never finish drinks that taste suspicious (especially if salty- GHB, or plasticky- GBL).

Although GHB or similar drugs may be used to spike drinks, a point to remember is that alcohol itself is by far the drug most likely to facilitate sexual assault and even in cases where GHB is involved alcohol is likely to be involved too.

GHB and GBL should not be mixed with other drugs, or with each other.

Mixing GHB or GBL with other drugs that depress the nervous system, such as alcohol, greatly increases the risks. Mixing with ketamine, opioids like heroin or methadone, benzodiazepines like diazepam, and other drugs that have sedating effects will also increase the risks.

Combinations with stimulants like cocaine could also add risk, as they make the user feel more awake than they would otherwise feel, allowing them to tolerate more GHB. If the stimulant then wears off more quickly than the GHB or GBL, this could result in unexpected coma.

1,4-BD is broken down in the body by the same enzymes that metabolise alcohol, so taking these two together may be particularly unpredictable and risky.

GHB and GBL can be addictive, typically when the drugs are used regularly for a sustained period. Taking GHB or GBL everyday results in increased tolerance, and users may become dependent on it. Those dependent on GHB and GBL usually suffer from cravings, anxiety, low mood, and have trouble sleeping if they do not re-dose every few hours.

Withdrawal symptoms start within hours of the last dose. The difficulty of withdrawal varies. Some may struggle with insomnia, jitteriness, and low mood, for others, withdrawal can be life-threatening, requiring intensive care. People who are addicted to GHB/GBL should not attempt to suddenly stop using it without medical assistance, as this could be dangerous.

Symptoms in the first days may include agitation, panic attacks, hallucinations, shaking, raised heartrate, and occasionally seizures and muscle breakdown. Depression, anxiety, and insomnia may continue for weeks or more.

There has not been research identifying any long-term health harms caused by consuming these drugs aside from the very significant ways that addiction itself can severely impact your quality of life. However, there have not been many people living with dependence on these drugs for many years, so the lack of existing evidence is not proof of a lack of harm.

How much are you taking?

Extreme caution should be used when measuring doses. Pipettes are often used to accurately measure a dose. GHB, when sold as a solution, varies in concentration, so it is very important to know how strong the solution is, however, there may still be inaccuracies. Always start with a very small dose.

Sensitivity to the effects may vary from person to person. If you buy or are given a pre-prepared solution of these drugs, the risks of accidentally taking too much is especially high. Taking an unmeasured dose of an unknown solution is very risky, even if it seems like a small amount. Measuring out doses millilitre by millilitre using a pipette, and starting with a small dose, reduces the risk.

Are you taking GHB or GBL on its own?

Never mix GHB or GBL with other drugs.

Just a small amount of alcohol combined with GBL can have strong negative effects. A high proportion of those who experience negative effects after taking GBL have also been drinking alcohol or using other sedative drugs.

Are you taking responsibility over the risks you face?

These drugs may be carried in quantities enough for several overdoses, so it may be safest to prepare in advance the quantity you wish to take in one session so that when intoxicated, you can only take up to an arranged limit.

Friends should always look out for each other – if someone is suffering negative effects, seek medical assistance immediately. If they cannot be roused, put them into the recovery position until you can get help.

Is GHB/GHB safe as long as it isn’t mixed with alcohol?

No. Many overdoses, deaths and harmful consequences have occurred with just GHB and GBL alone, although taking it with alcohol does radically increase the risks. People can develop severe addictions to GHB and GBL too.

Is GHB/GBL good for bodybuilding?

GHB and GBL are probably not effective ways of achieving bodybuilding aims. It is certainly not worth the risks of trying it out.
Before GHB began to be outlawed in many countries, it was promoted as a supplement for bodybuilders. This marketing was based on research showing that it stimulates the release of growth hormone during deep sleep. There have not been any studies that directly demonstrate that it helps bodybuilders to achieve the look they want. No studies have been conducted on the side effects or if there are any lasting benefits of using the drug for muscle growth.

However, tolerance to GHB builds up fast when used daily. It becomes difficult to sleep without using ever-greater doses. Therefore, addiction can result. The benefits of daily GHB for bodybuilding are not proven, but the harms are clear; bodybuilders have suffered from serious addiction problems from their GHB use.

Support our work and help ensure that evidence-based research can influence policy and public opinion, not political or commercial agenda.

Drug Science is an independent, science-led drugs charity. We rely on donations to continue to promote evidence-based information about drugs without political or commercial interference.

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Cocaine is a stimulant drug extracted from the coca plant which grows in regions of South America. In the Andean region the leaves, chewed or in tea, are believed to reduce the fatigue associated with the high altitude.

Cocaine comes in different forms with distinct risks attached.

Powder cocaine (hydrochloride)- usually snorted

This is the most commonly encountered type in most of Europe. The whitish powder contains cocaine in its ‘salt’ form, usually cocaine hydrochloride. Users usually crush and chop it into a fine powder, then snort little lines or piles of it up their noses. On average, about a quarter of the powder is actually cocaine hydrochloride; the rest is just filler and adulterants to boost profits. Some of these are less toxic than cocaine itself, (e.g. sugars) but plenty of other drugs have been identified mixed into cocaine. Sometimes very harmful chemicals have been found like levamisole  – a worming treatment used for livestock – which can have devastating effects on the immune and vascular systems, even leading to parts of the face dying.

Powder cocaine is also dissolved and injected by a minority of users. Injecting cocaine carries much higher risks than snorting it, or even smoking it. Overdose and death are more likely. Infections at the injection site and systemic infections like HIV are a risk. Given the typical low purity of cocaine, most of what is injected will be unknown substances. The effects hit hard but fade rapidly, so just minutes after injecting, users often feel a powerful urge to redose.

Crack cocaine- usually smoked

Smoking cocaine typically gives a faster, more intense rush of effects than snorting it, and is associated with a greater level of harms. Powder cocaine, the ‘salt’ form, cannot be smoked efficiently. Crack on the other hand is a crude form of cocaine ‘freebase’ that is made for smoking. It tends to comes in little yellowish, shiny nuggets, called ‘rocks’. They can vary in colour and texture. Smoking any substance can irritate or harm the lungs, and smoking crack can cause serious damage. The heat of a flame causes the creation of other chemicals, like methylecgonidine, which can increase harms. Whilst cocaine powder is widespread across many social groups, crack cocaine is usually associated more with disadvantaged and marginalised people, and the harms of crack addiction may be intensified further in the context of poverty. Crack cocaine reaches the brain and begins to cause effects almost immediately, whereas the effects take around 5-10 minutes to really get going when powder is snorted. This immediacy is part of what makes crack more dangerously addictive.

As well as smoking, some crack users inject, which requires the crack to be dissolved in a suitable acid first. Injecting is generally the riskiest and most damaging method of ingesting cocaine.

Coca leaves

The leaves of the coca plant, which contain small amounts of the drug, have minimal risks when used in traditional ways.

Cocaine is a plant alkaloid, which is a powerful central nervous system stimulant. It causes its effects by disabling mechanisms that mop up and recycle the noradrenalin, serotonin and dopamine released in the brain. This leads to a temporary increase in the amounts of these neurotransmitter chemicals, which stimulates many circuits in the brain. Dopamine is involved in ‘reward’ pathways in the brain, which is thought to be why cocaine can be highly addictive.

Currently cocaine has very limited medical uses as a local anaesthetic not a stimulant. For example, it can be an ingredient in a mouthwash to alleviate mouth sores and ulcer pain that can comes as a side-effects of chemotherapy in cancer patients. It also has some surgical uses, for instance nose or eye operations, but other drugs without cocaine’s side effects are usually preferred.

Typically, cocaine very quickly gives a surge of peaceful euphoria, alertness, and a feeling of power and energy. Users (especially when smoking crack) can feel intensely euphoric (the ‘rush’) and afterwards feel super-confident and happy, and urgently wanting to talk, dance, have sex, or otherwise do something with the energy they have. If the cocaine is very dilute, or the user has developed a tolerance, there may be little or no rush. With or without a rush, users typically experience pleasure, free-flowing ideas, and may talk very fast and excitedly. It usually makes users less interested in eating, but more interested in drinking alcohol and smoking cigarettes. Some people notice unpleasant effects too, like feeling anxious or impulsive, or finding the urgent rush of energy and raised heart-beat alarming.

Cocaine is also a local anaesthetic (hence its medical use), causing numbness of the throat and back of the tongue where it drips after being snorted, and a numb mouth when smoked. Sometimes people rub left-over cocaine on their gums which also numbs them. Other anaesthetising chemicals may be added to cocaine to disguise dilution, so the numbing feeling is not a mark of high purity.

Cocaine use typically has unpleasant effects too, as the chemical is cleared from the body, and the brain tries to recover its chemical balance. This is the ‘comedown’, where the user feels washed out, glum or grumpy, anxious or paranoid. Some users struggle to resist taking more cocaine to delay the inevitable comedown.

Whilst most users of powder cocaine manage to control their use so that they are less likely to experience serious harm, a significant minority find it very difficult to resist taking more, to see if they can push their euphoria higher, to recapture the initial rush, or to avoid the unpleasant crash of depression and anxiety that immediately follows moderate or heavy cocaine use. Users can binge, taking more and more every few minutes until their supply runs out.

Cocaine is one of the drugs that regularly causes death. It also causes thousands of emergency hospital admissions, often with chest pain. Most people who die from cocaine are long-term users who take large quantities and whose bodies, particularly the heart, may have been damaged. The risks are lower when doses are moderate and use occasional. However, cocaine can and does severely harm and kill otherwise healthy people without a history of regular use or addiction.

Taking cocaine raises body temperature, blood pressure and heart-rate, and narrows blood vessels. Bingeing on cocaine can result in heart attacks, strokes, organ failure, and seizures through overheating. Sometimes, a long binge can cause psychosis, especially if more is taken instead of sleeping.

Cocaine, especially when combined with alcohol, can make some people impulsive, arrogant and aggressive, contributing to violent crime.

Yes. Due to cocaine’s effects on the cardiovascular system, if you have a pre-existing heart issues, or high blood pressure, cocaine use will have higher risk.

If you have any underlying mental health issues such as psychosis, anxiety or depression, cocaine, or the comedown, may exacerbate symptoms.

Cocaine lowers seizure threshold so if you have epilepsy cocaine could provoke seizures.

Mixing drugs makes the effects on your body and mind even harder to predict and manage.

Many people who die after taking cocaine had also taken other drugs at the same time. Alcohol is very often taken with cocaine, but this combination is more dangerous than either drug alone. The two drugs react in the body to form another drug, called cocaethylene. This seems to cause a longer duration of effects which are stressful to the body. Alcohol increases the amount of cocaine that gets into the blood and by masking some of the sedating and confusing effects of alcohol with a stimulant, users may end up drinking more. Heart rate rises further than the drugs cause alone.

Injecting a mix of cocaine with heroin, called ‘speedballing’, is reported to give distinct and intense effects, but this practise is exceptionally risky and addictive. Cocaine masks the sedating effects of the heroin and makes users feel confident, so users may take an overdose of heroin without feeling the warning signs.

Mixing cocaine with other stimulants increases the chance of overloading your body somehow, causing overdoses and even death through heart attacks, getting overheated, having seizures, or the toxic effects of a flood of too much serotonin in the brain.

Taking cocaine could be especially dangerous when taken on top of certain medications, especially ones that work on the mind, such as MAOI antidepressants. Cocaine reduces seizure threshold, which means that it takes less to cause a fit when a person is on cocaine. In combination with Tramadol and other drugs which also reduce seizure threshold, there could be a high risk of seizures.

Cocaine, in all its forms, (excepting coca leaves/coca tea) is highly addictive, with injection and smoking crack generally thought to be the most addictive ways to take it. Humans and other animals generally enjoy cocaine intensely and want to repeat the experience. This desire in people seems often to override their awareness of the risks, and for some problem users, leads to crime to fund their habit. Some people use cocaine even when they are suffering from the effects that it is having on their life and health. Whilst the majority of people who use cocaine do so only experimentally or occasionally, a significant minority of people who try cocaine become addicted. Some users find it challenging or impossible not to binge, taking dose after dose, until they run out.

The brain responds to nice things like food and sex by releasing dopamine, which feels good and acts as a reward for seeking out those things. So dopamine is involved in the mechanism of the brain that tells use when something is good. One function of cocaine is preventing released dopamine in the brain from being mopped up again, so it builds up. This is very rewarding, producing a drive to seeking out and take more cocaine. Even so, drugs do not typically strip users of any ability to choose, and many people manage to limit or stop their use of cocaine when they suffer negative effects.

Addicted users who inject cocaine, use cocaine with other drugs, and have chaotic lives, are usually those who suffer the most severe harms. With injection, in addition to the very high risk of overdose and death, there is the risk of infected wounds, heart damage and blood-borne diseases like hepatitis and AIDS.

Bingeing on cocaine, especially when a user is neither eating or sleeping properly, can cause traumatic episodes of psychosis; for example paranoid delusions and realistic hallucinations that people are coming to arrest or attack you, or that insects (‘cocaine bugs’) are all over your skin.

Smoking cocaine (more precisely, inhaling hot cocaine vapour) can cause lasting damage to the lips, mouth and delicate lung tissues. So-called ‘crack lung’ can be both painful and disabling to lung function.

Snorting cocaine can cause destruction to the membranes, cartilage and even bone inside of the nose and head, sometimes causing holes in the septum (middle bit) of the nose, and very rarely holes all the way through the roof of the mouth. This, like ‘crack lung’, is partly because cocaine makes blood vessels contract, depriving tissues of the oxygen and nutrients needed to repair damage caused by the toxicity of the drug and the chemicals it can be mixed with.

Cocaine can cause you to compulsively pick at and scratch skin, producing wounds. Taking cocaine can make people anxious and paranoid; it makes nerves more sensitive, and can stop problematic users getting the diet they need to maintain physical health. These effects combine to make people itch and injure themselves in compulsive attempts to get rid of itches and even imaginary insects in the skin.

The highest rates of addictions to cocaine and crack are found in sections of society suffering from deprivation and joblessness. Harmful drug use is often part of a vicious circle, both contributing to, and resulting from the problems in people’s lives. People who are addicted to cocaine are likely in many countries to be arrested and imprisoned. A criminal record can make it harder to break the cycle that damages families and communities as a whole. Addiction can promote crime in order to buy drugs.

Taking cocaine always carries dangers, and the only way to avoid harm is to avoid taking it. The highest rates of harm caused by cocaine are suffered by a small proportion of addicted users who persistently take large amounts of cocaine, often by smoking or injecting it, often with other drugs. Occasional social users are taking a risk, but they are less likely to get harmed, if they can avoid addiction.

What are you taking and how?

The riskiness of cocaine use varies hugely. Be very cautious about how much you consume, remembering that because purity is so variable, a line from one batch could be the equivalent of 5 lines from another batch. It is always possible to take more, but never possible to un-take what you have already taken!  Snorting cocaine is thought to be less frequently harmful than injecting it or smoking crack.

Could you get addicted?

Anyone can get addicted. Having a little, once in a while, with other people around is obviously less risky than taking it in uncontrolled amounts, regularly, alone. However, the addictive qualities of this drug make it quite easy for moderate, social use to slide into chaotic, constant use. Being very vigilant over your use is vital. If you are taking more and more cocaine, more and more regularly, you may be on a slippery slope, as tolerance builds up encouraging higher doses, and cravings intensify. If you are struggling to control your use, or think you are addicted, seek professional help. The earlier you get help, the better the chance of avoiding lasting harm to your life.

Are you considering the harms cocaine can cause to others?

Cocaine addiction often spreads through social and familial networks. Many people who end up struggling with the harms of the drug first try cocaine when it is shared by well-intentioned friends and family. If you offer cocaine to others, there is a small but significant risk that the recipient will become addicted as a direct or indirect result.

European consumption of cocaine fuels the demand that leads to thousands of deaths in South and Central American conflicts between the gangs involved in the drug trafficking, and between them, armies and police forces.

Is cocaine a great drug for sex?

Cocaine is used to enhance sex, but the risks and unwanted effects could outweigh any benefits. Some people report feeling higher sex drive and more sexual confidence on cocaine, and cocaine can give people stamina. However, it affects judgement, reduces inhibitions and increases impulsivity, which raises the risks of regretted experiences and harm.  Cocaine can lead to unsafe, unplanned or rougher sexual behaviour, with less condom use, risking unplanned pregnancy, injuries and leaving users susceptible to HIV, Hepatitis B and other sexually transmitted infections. For men, it can also impair ability to achieve and sustain an erection, and make it very difficult to orgasm. There have been rare and painful cases of priapism (when an erection doesn’t pass) from cocaine use. This problem has required surgical intervention that can permanently damage the organ and its function.  Sex and cocaine both put added pressure on the heart.

Any short-term benefits should also be balanced against potential long-term harms. People addicted to cocaine often lose interest in sex entirely, or suffer erectile problems.

If it looks good, and powerfully numbs my mouth, is it reliable stuff?

No, it’s virtually impossible to know the purity of cocaine without sophisticated drug testing equipment. Most cocaine contains many fillers and adulterants that can themselves be harmful. Often, other drugs with numbing effects are added to hide the extent of adulteration.

Support our work and help ensure that evidence-based research can influence policy and public opinion, not political or commercial agenda.

Drug Science is an independent, science-led drugs charity. We rely on donations to continue to promote evidence-based information about drugs without political or commercial interference.

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Cannabis is a drug that comes from a plant, or a plant which is used as a drug. Cannabis use has been falling; most people in the UK (more than two out of three) have never tried cannabis, but it’s still the most popular illegal drug.

Cannabis comes in many different forms. Its users are varied too, taking the drug in different ways, for different reasons. Some people use it looking for fun and laughter, some hope for medical benefits, some want help to relax. Some people use cannabis out of habit or because they find it difficult to resist. Cannabis can deliver the positive effects its users hope for, but it doesn’t always do so, and it can cause harm too.

This page will let you know some of the risks of cannabis use that users can easily avoid, and also help you to recognise those risks you can never totally get away from if you use it. With this information, it’s easier to make informed personal decisions about whether it’s worth the risk to use cannabis at all, and if you do use it, to keep those risks as low as you can make them.

It’s hard to say how harmful the use of a drug like cannabis is ‘overall’, because it depends so much on the user, how they use it, and even the type of cannabis. Most people who try cannabis are not harmed by it at all. However, cannabis can play a very destructive role in some people’s lives, particularly if they become addicted to it. Regular users sometimes notice that cannabis is damaging their physical or mental wellbeing, others feel it holds them back from fulfilling their potential. As with any drug, the only relationship with cannabis that is 100% safe is avoiding it entirely. However, if somebody wants to enjoy cannabis and accepts the possibility of harm, there are many important choices that can reduce the risks. There are powerful choices to be made about what cannabis to use, when and how to use it.

An analysis by Drug Science which added up and compared the harm caused by 20 different drugs in the UK placed cannabis roughly in the middle; it causes more harm to society than several other illegal drugs (mostly because there are many more users) but less harm to its users than the legal drugs tobacco and alcohol, both of which have a higher potential to cause serious illness and death. This study estimated the total harm done by cannabis in 2010 in the UK. Another study by Drug Science also looked at how changing governmental legislation on cannabis can reduce harm to users and found that state control of cannabis was the best policy to minimise drug harms.

Therefore, better political choices could make cannabis safer overall.

Similarly to alcohol, cannabis can help people relax and feel pleasantly sleepy and ‘stoned’, or in another setting, people use it to socialize, feel ‘high’ and laugh. It can make people clumsy with their bodies and words. Less like alcohol, cannabis also can alter the senses in unusual ways, so music, food, films, computer games might seem different, more fascinating, and easier to feel immersed in.

Cannabis has some side effects such as drying out the mouth and eyes (which can look red and feel itchy), and generating a strong appetite; ‘the munchies’.

Especially for someone who has never taken cannabis before, the effects can be hard to predict, and can be unpleasant for some people. It’s common for people to try cannabis and not want to use it again.

Taking cannabis has the effects it has because it contains some unique drug chemicals called ‘cannabinoids’. The cannabinoid which is most important in making someone ‘stoned’ or ‘high’ is called THC. Some cannabis varieties (such as skunk) can contain much more THC than other types, and so give stronger effects or can be used in smaller amounts. However, scientists and cannabis users are also discovering that it’s not just the amount of THC that is important, but also the balance of THC with other cannabinoids, especially one called CBD. Cannabis varieties with lots of CBD (like most ‘hash’) might feel different (more relaxing, less confusing) and have a lower chance of causing harm, than cannabis varieties with little CBD (such as skunk). This is because CBD interacts with THC and reduces its “stoned” effects.

Our minds respond to cannabinoids from cannabis because we have a system in our brains called the endocannabinoid system that it can interact with. This system has a role in controlling memory, mood, appetite, sleep and other functions. The endocannabinoid system is not there to be triggered by cannabinoids from cannabis; the fact that it can be manipulated by this plant may be due to a close co-evolution of humans and the cannabis plant family.

The endocannabinoid system responds to the body’s own endocannabinoids; these are cannabinoid chemicals made in our brains. The effect of cannabinoids from cannabis on the endocannabinoid system doesn’t entirely explain how cannabis users feel and act when they are stoned. Without realising it, people learn to fit in with acting a certain way when they are stoned and around other stoned people. This helps explain why one substance, in different cultural contexts, can have such different effects.

The two main ways that people get the cannabis chemicals into their body are through the lungs, by smoking or vaporizing it, or through the gut (orally), by eating or drinking it or by holding cannabis oil under the tongue.

The effects of cannabis when smoked or vaporized appear almost immediately, reach their strongest in the first 15 minutes or so, start to fade before an hour has passed, and are nearly gone after about 3 hours, although the exact timings vary from person to person.

When used orally, the effects of cannabis take much longer to appear and rise to their peak, you might feel nothing for an hour. Then the effects can last 5 hours or even more. This time can be very different from person to person.

The under-the-tongue route produces effects roughly half way between vaping /smoking and oral use.

The commonest way of using cannabis in the UK is also the worst for your health. That is adding it to tobacco in a cigarette paper, rolling it with no filter and smoking this ‘joint’. Tobacco smoke can give you lung cancer, COPD, and other potentially deadly diseases. Tobacco is also addictive, much more so than cannabis, so smoking cannabis joints can be a ‘gateway’ to a harmful and expensive tobacco addiction. Or it might lead you to craving more joints, and so smoking more cannabis than you might otherwise. Smoking cannabis as well as tobacco might lead to more harm than smoking tobacco only.

Smoking cannabis on its own (in a pipe or bong for example, or rolled in a tobacco-free cigarette) is much less harmful. The risk of lung cancer is far lower, maybe as low as someone who doesn’t smoke at all. Also, using tobacco makes it harder to breathe deeply and freely, cannabis alone seems not to. However, burning any plant, cannabis or tobacco, makes hundreds of toxic chemicals, and a cannabis smoker is still breathing in this cloud full of little irritating particles. This can cause inflammation, coughing and wheezing (bronchitis, which goes away when a user quits). How badly cannabis affects the lungs depends, of course, on how much someone uses it. People who smoke occasionally might not notice any problem, but constant cannabis smoking might do damage.

People who want the rapid effects of inhaling cannabis without the smoke can use a vaporiser instead. Vaporisers heat up the cannabis hot enough that the cannabinoids and some other substances evaporate and can be inhaled, but not so hot that the plant material is burnt. The vapour can still make you cough, but there is some research now to show that it can cause less harm. Moreover, avoiding the chemicals that result from burning is likely to be a good move.

Cannabis can also be cooked into food (such as brownies). This avoids any risk to the lungs, but a possible downside is that the effects can take a long time to come on and can take longer for some people than others, making it much harder to judge how much to take. This can lead to taking way too much and having a horrible few hours.

The immediate effects of cannabis can be nasty but are rarely catastrophic. Let’s start with common unwanted effects, things which might sound familiar to many people who have tried the drug.

Taking too much too fast (which is easy when the cannabis is very strong) can be horrible. Someone may suddenly look and feel pale, shaky and ill, (sometimes called greening out, or pulling a whitey) they may even vomit or collapse. This effect can be a result of a rapid drop in blood pressure. It’s a good reason to smoke at a slow pace, to get a feel for the strength of the cannabis. If someone does feel ill, it usually doesn’t last long and the person may recover faster if they lie down with their feet up. Whatever the drug is, never leave someone alone who is vomiting and intoxicated, as there is a risk of choking. If they are vomiting and intoxicated make sure their airways are cleared and consider putting them in the recovery position. Combining cannabis with alcohol or other drugs creates a higher risk of feeling awful and regretting it.

Even people who have enjoyed using cannabis before can unexpectedly find that it gives them bad rather than good feelings. Sometimes people just feel overwhelmed and might need to lie down for a bit, especially if they get more stoned than they intended to. Even when taking a typical amount, the same as you might have enjoyed before or the amount that your friends are enjoying, users might find that they feel worried, suspicious, sad, confused or even feel trapped going round in circles of weird thoughts.

Usually, if someone becomes panicked, confused, or behaves oddly when intoxicated on cannabis, they will be alright given time, especially if they are reassured and guided to breathe slowly and relax. Sometimes, they will feel fine after a few minutes, sometimes they will not feel good, but will be able to hold out with some friendly support until they sober up a bit. Very very occasionally, if someone remains very frightened or paranoid, and does not seem to respond to reassurance, or their behaviour is very alarming, it may be sensible to get help, for example by calling an ambulance. This can be a difficult judgement to make, remember that the good or bad effects of cannabis usually start to decline on their own after about an hour after inhalation, or a couple of hours after eating it.

It can be common for people who are intoxicated on cannabis (especially strong ‘skunk’ strains which are high in THC and low in CBD) to say things or feel things which are just like symptoms of psychosis, for example to think other people are talking about them or being paranoid. Experiencing some psychotic symptoms whilst stoned isn’t the same as actually being psychotic. However, if you or someone else should have sobered up, but are still feeling paranoia or delusional ideas, it is important to get medical help. Extremely rarely, getting intoxicated on cannabis can trigger a mental health crisis such as a ‘psychotic episode’, which carries on even after the person should have sobered up. This can be a serious situation, and they need to have medical assistance to give them the best chance of getting better fast without any lasting effects. This usually only happens to people who already have a vulnerability to mental health problems. Most people who have a psychotic episode triggered by cannabis (or anything else) recover well over the next few days with treatment. However, having this type of reaction to cannabis even once is a strong indication that continuing to use cannabis could be very harmful. There’s more information on this in the section Will cannabis make me lose control of my mind?

Cannabis is one of the least toxic drugs. Unlike drugs such as alcohol, paracetamol, heroin or ecstasy, users do not die after accidentally taking too much. But like all drugs that distort the way you think and behave, cannabis use creates a risk of hurting yourself doing something stupid, ranging from trying to cook to trying to cross a motorway. People who drive stoned double or triple their risk of crashing, injuring and killing others as well as themselves.

Occasionally after using cannabis, people feel their heart flutter, skip beats, race or pound in their chest. These unpleasant but usually harmless feelings (called palpitations and tachycardia) can be scary, especially as cannabis can make sensations feel more intense than usual, and make anxiety worse. Of course, when someone gets scared by this effect, it can make the heart beat even harder and lead to a panic attack.

Cannabis use does put some extra stresses on the body, and there is some evidence suggesting that heart attacks and strokes are slightly more likely to happen soon after using cannabis, just as they can be triggered by exercise or sex. This is a tiny risk that is not relevant to most users, but people with health problems (like an irregular heartbeat) should always be aware that drugs might have greater risks to them.

Cannabis smokers sometimes do some unnecessary things involving breath-holding, either as part of smoking games or in the mistaken belief that holding in the smoke will get them higher, faster. Struggling to hold your breath when you want to cough or breathe out can create sudden pressure changes in the lungs, as can sucking very forcefully from a bong. These habits have led to surprising lung injuries , where air has forced its way through tiny tears in the lung and ended up in places where it shouldn’t be, but these injuries are rare.

Using cannabis when pregnant could have effects on the foetus. The baby might weigh less when it is born, and the child might have a bigger chance of having behaviour problems and doing worse at school as it grows up. More research is needed to be sure about this.

Most of the serious harm caused by cannabis use is suffered by the minority of users who use it regularly, who take it daily or nearly daily, not to the majority of users who like to have some now and then. Like alcohol or fast food, the most important thing is staying in control, not letting cannabis become an essential part of your lifestyle. Using less is the simplest and most effective way to avoid harm. Another way is by understanding the relative THC content of the cannabis you smoke. Strains with higher THC are likely to cause more damage and so minimising these strains, where possible, will go a long way to reducing negative effects.

Don’t be discouraged from cutting down by the thought “I smoke loads of cannabis; if I smoked half as much I’d still be smoking loads”. In fact, halving the amount you consume will probably take away more than half of the risk.

It used to be thought that cannabis isn’t addictive. Now it is clear that this is not true at all, about 9% of people that have used cannabis will become addicted. Some people choose to use cannabis frequently but fit it around their life and can take a break from it easily, but others can’t go without it and find that it has become a real problem in their life. People who live alone, have gone through recent difficulties like money troubles, and who use cannabis to cope with their problems are most likely to get addicted, but it could happen to any heavy user.

Addictions to different drugs have very different consequences. People who are addicted to alcohol can become very ill and even die if they are unable to drink it. People who are addicted to cannabis don’t get seriously ill without it, but might find it just as hard to quit the drug or regain control over their use. A person addicted to cannabis can become irritable and anxious if they try to go without it, lose their appetite, and feel unable to relax and sleep. These effects get considerably better after the first three days. Going to your doctor can help you access support towards finding a way to overcome cannabis addiction. People trying to quit cannabis also support each other online.

A small number of people who smoke lots of cannabis get an illness where they feel sick, have stomach aches and vomit. Mysteriously, these people usually find that very hot baths and showers help a bit, although stopping cannabis use is the only known solution. This illness is called Cannabis Hyperemesis, and in one case, the vomiting was violent enough to tear a hole in the oesophagus (food pipe).

In the UK, the thing about cannabis use that is most talked about by politicians and written about in newspapers is the fear that it can make young people become mentally ill, and maybe never recover. There is some truth and often plenty of exaggeration to these concerns. To put it in proportion, for most young people experimenting with cannabis, the risk of going on to become addicted is much higher than the risk of going on to develop serious mental illness such as psychosis. Psychosis is most clearly linked to very heavy use of cannabis like ‘skunk’, which has lots of THC in it (making it strong), but almost no CBD (a protective chemical). Using cannabis with lots of CBD in it, like most types of hash, might not be linked to psychosis at all. In fact, CBD on its own has been tried out as a treatment for psychosis, and results are promising.

For some people, this issue should matter more because the risk of cannabis provoking psychosis will be higher for them. For example, if you have a close relative who has had episodes of psychosis, or has schizophrenia, cannabis might be enough to give you a push towards developing such conditions yourself.

To understand the risk, you have to understand a little about what psychosis is and what causes it to develop (often in early adulthood). Someone with psychosis may experience paranoia (e.g. thinking people are plotting against you) delusions (e.g. thinking that you have a mission, and are being sent guidance through the radio) and hallucinations (e.g. hearing voices). Most of us are very unlikely to ever get psychosis, but this depends on a combination of our genes and the life we live.  In a world in which no-one used cannabis, people would still develop psychosis, sometimes this is a one-off episode of a few days or weeks, sometimes someone dips in and out of periods of psychosis over their lifetime, sometimes it is more or less constant, and occurs with other problems (schizophrenia). All of us have an inbuilt genetic risk for psychosis that ranges from virtually zero up to a maximum of more than 50% (the risk if your identical twin has schizophrenia). Then, on top of that inbuilt risk, things in our lives act as nudges towards or away from psychosis developing.

Someone with a high genetic risk might only need a little nudge, someone with a lower risk may need many nudges all added together for psychosis to emerge. These nudges towards psychosis can include challenging, isolated lives, losing a parent, facing hostility (e.g. the stresses of being a gang-member or a struggling immigrant) stressful events (like having a baby), or even just living in a city. It has become clear that THC in cannabis should be added to this list. Heavy use of high-THC cannabis like skunk seems to nudge people towards developing psychosis, makes it appear earlier in people who might have got it anyway, makes psychosis worse in people living with it already, and makes it harder to recover.

Overstating the role of cannabis in psychosis could be as harmful as ignoring it. For young people who are developing psychosis, a supportive, open, understanding family environment works against psychosis and for recovery, whilst a hostile, blaming response worsens the outcome. People in the process of developing schizophrenia often turn to cannabis, (rather than the cannabis causing the illness) possibly because it feels like it helps them in dealing with some of the symptoms. Understanding their perspective, recognising that cannabis alone is unlikely to have caused the problem and supporting them to live without cannabis (or first to swap skunk for hash) is a more helpful response than angrily blaming them, and considering their life ruined.

Being a cannabis user or being addicted to cannabis seems to go along with problems like depression and anxiety a bit more often than would happen just by chance. It is hard to work out though whether the cannabis causes these problems or if the cannabis use is a result of them, and individuals are using it to self-medicate. It can also be both the drug use and the problems that are caused by something else entirely. Looking at the best evidence on this question, it seems that heavy cannabis use, especially from a young age probably does increase an individual’s chance of becoming depressed or suffering from an anxiety disorder, although the increase is not huge. In fact, more recent studies are finding that CBD, one of the chemicals in cannabis is particularly effective at combatting anxiety disorders but to date there is limited data on its effectiveness as a treatment for depression.

We have written blog post on this topic. Once again, it depends. Scientists have shown that if someone young is addicted to cannabis for a long time, maybe smoking it at least several times a week while whilst they are still at school, they might end up doing quite a bit worse on intelligence tests. On average, cannabis users do less well at school and leave education earlier too.

Chemicals in cannabis might directly interfere with the long slow development of an adult brain, which doesn’t finish until people are in their mid-twenties. Cannabis interferes with memory, so someone might not do well if they try to learn whilst stoned, or even the day after being stoned.

However, cannabis might not be the direct cause of lower achievement, or not the only cause. Researchers looked at twins who differed in their cannabis use but had the same family background, it was the disadvantaged background not the cannabis use that made the difference to their success. Another reason might be that the unfair ‘stoner’ stereotype of lazy, muddle-headed cannabis users (especially young males) subconsciously affects how they start to think about themselves or lowers the expectations other people like teachers have of their abilities, actually leading to lower achievement.

At any age, becoming addicted to a drug makes it harder to succeed in many parts of life. Regularly using drugs such as cannabis can hold someone back simply by using up their time, and re-ordering their priorities, even if the drug itself doesn’t damage the brain.

Some types of cannabis might be more likely to hold young people back. Cannabis with lots of THC and no CBD seems to be more addictive and have worse effects on memory.

To summarise, using lots of cannabis while still young (especially being addicted) could prevent someone reaching their full potential. However, there are many successful and intelligent cannabis users. The same research that found that long-term heavy cannabis use when young might make people less intelligent seemed to show that once people are grown up, starting to smoke cannabis probably doesn’t affect their intelligence. Stereotyping cannabis users as slow thinkers and underachievers can make things worse, because people have an unconscious tendency to be limited by negative stereotypes.

Yes. Cannabis has been used as a medicine for thousands of years and is helping increasing numbers of people now. But some people misunderstand what this means. Sometimes people argue with one side saying “cannabis is a harmful drug” and the other side saying “no it isn’t, cannabis is a wonderful medicine”. Both sides are right and wrong. Cannabis itself isn’t either good or bad; it depends on the type, how it is used, in what situation, and who uses it. It is just like a knife; a surgeon can use one kind of knife to make a sick person better, or a healthy person can accidentally harm themselves with a knife.

Usually, for a drug to be recognized as a proper medicine, scientists have to have done a trial in which they take a group of people who all have a particular problem or illness, give only half of them the drug, and find out if the people who were given the drug do better overall than the people who were not given it. A recent study reported that in the UK nearly 1.4million people are using cannabis for medical reasons. Although cannabis is still illegal it seems that many people are finding a benefit from it. Recently, there has been growing interest in looking at real world accounts of these people and reporting on how medical cannabis has helped them. Scientists conducting this kind of research, which is one of the things we do at Drug Science, argue that this is a reasonable and high-quality way of understanding how well a drug is doing. We are working with legislators to realise the importance of studies that don’t follow strict and expensive trials and they are beginning to see the benefit of this new approach.

Drug Science is currently collecting data on medical cannabis with Project Twenty21, through which eligible people can access medical cannabis at a reduced price, while their treatment outcomes are analysed to gather evidence for the role of cannabis as a medicine and to help guide public health policy.

Some forms of cannabis or chemicals from cannabis have passed through the strict trials showing for example that it can help reduce painful symptoms for some people with MS. Other medical uses of cannabis, like preventing seizures, seem very promising. Other evidence has also emerged on its role in treating chronic pain and anxiety and other psychiatric disorders.

But not everyone can benefit from the medical properties of cannabis, and trying to use it as a medicine without a doctor’s guidance might do more harm than good.

There are many scientists who are trying hard to help patients by investigating and testing all the interesting chemicals in the cannabis plant that could maybe work as medicines, so that as many people as possible can benefit in future. This work takes a long time, especially as research and medical use of the drug is restricted by the law. This leads to a very sad situation where people who might possibly benefit from using a carefully produced cannabis medicine like Sativex cannot get it from their doctor or can only buy unpredictable illegal cannabis.

The distress this causes is made worse when people put their hope in stories, which often spread online, that cannabis is a miracle cure for cancer and almost everything else. These stories are often passed to ill people with good intentions, but they can be a dangerously persuasive mix of misinterpreted facts and total nonsense. They can mislead people into thinking that radiotherapy and chemotherapy are evil treatments that don’t work, their doctors are their enemies, and that all a person with cancer needs is natural cannabis.

There is early hope that cannabis may have an important place in the toolkit doctors have to fight cancer, in short, it may become a useful chemotherapy, but it is not a replacement for current chemotherapy. At the moment, the evidence for cannabis as a chemotherapy is incomplete and uncertain, it might help, it might not. But it is certain that despite the damage they can do, the chemotherapies and radiotherapy in use now have helped millions of people beat cancer or extend their lives.

Cannabis is a Class B drug in the UK. That means that in theory, getting caught by the police with any amount of cannabis can lead to up to 5 years in prison, an unlimited fine or both. However, this political classification of cannabis is not a good guide to its harmfulness compared to other drugs or to the likely legal consequences of getting caught with it.

The first time that the police find cannabis in someone’s possession, they are likely to give a ‘cannabis warning’, and each time afterwards they will take tougher action, such as fining you, or arresting you. It is very unusual in the UK for someone to go to prison just for possessing cannabis for personal use.

Growing cannabis or selling it to others can result in more serious consequences. Remember that the law doesn’t distinguish between dealing cannabis and sharing or giving it to your friends, it all can be counted as supplying the drug.

Getting a criminal record for a cannabis offence can have many bad consequences. It can make it harder to get your dream job or can mean you can be blocked from travelling to some countries such as America. It might make it harder for you to become Prime Minister and produce great laws to minimise the harms of cannabis to society – even though many Prime Ministers and world leaders have admitted to using it!!

Any time you have an opportunity to use cannabis, make sure you are making a thoughtful, deliberate yes or no choice that you can justify to yourself. If deciding not to use the drug doesn’t seem like a realistic option freely available to you, because you are under pressure from other people or if you are perhaps becoming addicted, recognize that your power to limit the risks you face is being threatened and see what you can do to escape that situation.

Remember that your choices go well beyond yes or no. If you are young and think you might like to try cannabis, you don’t necessarily need to say yes at the first opportunity; waiting until you are older reduces the risks, and waiting for a perfect relaxed opportunity rather than the first available chance makes it more likely you’ll enjoy it anyway. If you have chosen ‘yes’ to cannabis use, that firmly closes the door on avoiding risk entirely, but opens up a range of new choices you can make to push those risks down; the hows, whats, whens and whys.

Perhaps consider some or all of these questions:

  1. How am I consuming my cannabis?
  2. Could I switch from smoking to a less harmful method?
  3. Can I avoid mixing it with tobacco?
  4. Would I be satisfied using less, or saving some for another time?
  5. When am I using cannabis?
  6. Is this a risky time and place to get stoned?
  7. Will I need to drive or be responsible for others in the next few hours?
  8. Am I using it more than I used to?
  9. Can I set myself a limit?
  10. Am I taking long regular breaks to confirm I can do without it?
  11. Could I be pregnant?
  12. What cannabis am I using?
  13. Would I prefer something a bit less strong?
  14. Could I find and switch to a lower-risk type of cannabis such as hash?
  15. Why am I using it?
  16. Do I really want this one?
  17. Am I just rolling a joint out of habit?
  18. Could I be becoming addicted?
  19. Could I be equally happy doing something else?
  20. Am I feeling under pressure to fit in?
  21. Am I getting stoned to avoid dealing with something?

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Caffeine (1, 3, 7- trimethylxanthine) is a toxin that some plants produce to defend themselves. Small amounts are not harmful to humans, but have stimulant effects, making users feel more alert and energised. Typical use of the drug comes from caffeinated drinks such as coffee and tea, and also soft drinks such as cola and ‘energy drinks’.

Like other stimulant drugs such as cocaine, caffeine in high enough doses can harm and kill. However caffeine use is very much safer and more manageable than the use of cocaine and other potent stimulants, and only exceptionally rarely causes serious harm.

Caffeinated drinks (generally low risks of harm).

Caffeine is found in drinks like coffee, tea, and mate (a tea drunk in Argentina). Caffeine can also be found in ‘energy drinks’ which have high caffeine content, and some soft drinks. In Europe, drinks (not based on coffee or tea) with a caffeine content of more than 150 mg per litre, have to be labelled as high caffeine content with the amount of caffeine on it.

Shops also sell caffeine shots, which are small amounts of sugary drink with a high caffeine content. Like alcohol shots, it is easy to drink a lot of these quickly before realising you have had too much.

It is common to become addicted to caffeinated drinks, in that stopping use will lead to withdrawal symptoms, although most people would not find it difficult to stop caffeine use.

Caffeine is often listed as a flavouring on soft drinks, although it may not be the case that caffeine adds to the taste of the drink, rather it increases the desire to consume it.

Caffeine tablets (low risk if used according to directions, potential for overdose if misused)

Caffeine tablets are legal and are used to increase alertness. Some beliefs about their effectiveness, for example in improving exam performance, are not wholly supported by the evidence. They do not replace the need for sleep, in fact a nap can be much more beneficial.

Caffeine as an adulterant in illegal drugs (could sometimes be harmful)

Analysis of drug samples show that caffeine is commonly added, which adds bulk cheaply and so increases the dealers’ profits. Caffeine has been identified in heroin, where it may make the drug easier to smoke. It is commonly added to stimulant drugs like cocaine, amphetamine (speed) and MDMA (ecstasy) where its stimulant effects may disguise how impure the drug is, and may also increase the risks.

Caffeine hinders the action of the adenosine. Adenosine dampens down brain activity, so by getting in its way (competitive inhibition) caffeine stimulates many circuits in the brain.

Caffeine also works because we have powerful beliefs about its properties. If you consume caffeine without believing something like “I’m consuming caffeine which will make me more alert”, the caffeine may not increase your alertness at all.

Caffeine has stimulant effects and makes people more alert, reducing feelings of tiredness. It is widely believed to improve mental performance but the evidence for this is mixed.It has been suggested that the appearance of performance enhancement is because caffeine reverses withdrawal effects in regular users rather than improving overall mental ability. In people who are not regular users, any improvement is likely to be counteracted by anxiety and jitteriness which make it difficult to focus. Caffeine may in some circumstances increase a feeling of alertness whilst actually decreasing ability.

Caffeine causes sweating and also makes people urinate more, although tolerance to this effect develops quickly so people who, for example, drink coffee every morning usually do not find this to be a problem. Caffeine can also lead to difficulty sleeping (insomnia).

Some people become anxious or irritable after caffeine. Unpleasant feelings become more likely the higher the amount you consume.

Caffeine has a few medical uses. Its stimulant properties mean it is sometimes useful to keep premature babies breathing.

Caffeine is also an ingredient in common over the counter medications for flu, colds and headaches. It can sometimes make pain relief drugs work more quickly and effectively, and can cou