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.

 

Duration:

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

 

Effects:

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.

 

Tolerance

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.

 

Setting

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 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.

Sitter

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.

Sitter

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.

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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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

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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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.

Chewing

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.

Smoking

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 Erowid.org 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.

Injuries

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.

Fresh

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.

Dried

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.

Powder

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

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

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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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.

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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

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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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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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.