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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Nitrous Oxide (Laughing Gas) Molecule Chemical Structure

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Be extremely cautious with the dosage

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

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

Avoid mixing it with other drugs, especially alcohol

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

Be prepared

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

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

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

Watch out for the possibility of addiction

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

Related Content

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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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GHB

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

GBL

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

They are all central nervous system depressant drugs.

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

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

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

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

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

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

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

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

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

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

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

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

GHB has two main medical uses.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

How much are you taking?

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

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

Are you taking GHB or GBL on its own?

Never mix GHB or GBL with other drugs.

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

Are you taking responsibility over the risks you face?

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

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

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

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

Is GHB/GBL good for bodybuilding?

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

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

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Benzodiazepines are sedative drugs which have been used in medical contexts since the 1960s to treat severe anxiety and insomnia. They are sometimes referred to as ‘benzos’ or BZD/BDZ, not to be confused with BZP (benzylpiperazine) and ‘benzo fury’ (benzofurans).

There are a wide variety of benzodiazepines which differ in the balance and length of effects. The most well-known types include diazepam (Valium), temazepam, and nitrazepam. The names usually end in –pam or –lam.

Benzodiazepines are available as tablets, capsules, and suppositories.

Very rarely, some users may inject liquid benzodiazepine or snort crushed tablets. These are more dangerous routes of consumption and can lead to rapid overdose, which can be fatal.

Not all benzodiazepines used recreationally are diverted pharmaceutical products. Illicitly manufactured benzodiazepine tablets are frequently being encountered due to availability from the internet. These may resemble pharmaceutical preparations, sometimes sold in blister packs, but are as unreliable as any other drug on the unregulated market. The content of these preparations will vary and may not even contain any of the desired drug.

Benzodiazepines increase the effects of Gamma-Aminobutyric Acid (GABA) on the brain. GABA reduces activity of the brain in areas that control memory, reasoning, and essential functions such as breathing. Therefore, benzodiazepines make the user feel relaxed and sleepy, reduce anxiety and cause muscle relaxation. This makes them very useful for treating conditions such as anxiety or panic attacks, where certain parts of the brain may be overactive.

Due to their sedative and calming effects, benzodiazepines are used short-term to treat sleep problems and anxiety disorders. They are also used to ease distress, panic, and fear.

Benzodiazepines relax muscles and have anticonvulsant effects, so are useful in treating the withdrawal effects of alcohol, where they work to ease agitation as well as preventing seizures, muscle spasms and shaking.

Benzodiazepines are not often used long term due to an increase in risks when used over a sustained period of time.

Benzodiazepines reduce anxiety, relax the mind and muscles, decrease alertness and concentration, and reduce coordination. Depending on the dose and the individual, benzodiazepines can cause cosy sleepiness, or calm chattiness. At higher doses, the sedating effects become stronger, and benzodiazepines can make a user’s speech slurred, cause confusion and can lead to a loss of consciousness. They can also cause amnesia, or ‘blackouts’, where the user later has little or no memory of what has happened over a certain period of time.

Very occasionally, benzodiazepines can have paradoxical effects (opposite effects to those desired). For instance, aggression, anxiety, delusions, and depersonalisation. These paradoxical effects are more common amongst children and older people. The exact mechanism of paradoxical effects is unknown; however, it is thought that there is a genetic link which makes a person predisposed to experiencing these effects, as well as a link to a history of alcoholism.

Using benzodiazepines poses risks to both physical and mental health.

If someone takes an overdose of a benzodiazepine, they can suffer unpleasant and potentially harmful effects. Overdoses can lead to confusion, slurring of speech, sleepiness, loss of coordination and collapse. If someone has taken enough to become unconscious, there is a risk of inhaling and choking on stomach contents which can potentially be fatal. Breathing can sometimes be depressed, especially in children. Severe, lasting harm or death from a benzodiazepine overdose is rare.

The danger of severe harm and death is very much greater if a benzodiazepine is taken with other sedative drugs such as alcohol, heroin or GHB. In these combinations, breathing can be depressed or stopped completely.

Emergency medical assistance should be sought when someone becomes unresponsive after taking drugs.

To reduce the risk of overdosing on benzodiazepines, try to carefully monitor how much you are taking. Starting with just half (or a quarter) of a dose and seeing how you feel can prevent you from taking too much all at once. It is a good idea to have someone who you trust around when taking benzodiazepines so that they can help you if you experience any negative effects. It is also possible to buy reagent test kits which can confirm or rule out the presence of a benzodiazepine. These are useful if the benzodiazepines intended for use have been illicitly obtained.

Benzodiazepines decrease control and impair judgment, meaning activities like driving under the influence of benzodiazepines can potentially be very dangerous.

Use of benzodiazepines can increase the risk of suicidal thoughts, especially in those who are addicted to alcohol or opioids.

Use of the benzodiazepine, Rohypnol (flunitrazepam), has been implicated with sex crimes. Concerns have been raised that victims’ drinks have been spiked with Rohypnol, making them very drowsy or even causing them to fall unconscious.

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

Taking benzodiazepines, particularly taking them regularly, may put someone at a greater risk of accidents. Doctors make a considered decision before prescribing them to people with impaired balance and coordination, who are at risk of falling or who may be severely injured if they do. It is also possible that long-term use of benzodiazepines could contribute to, or worsen, memory related problems or certain forms of dementia. Further scientific study is needed as it is unclear if such effects would be reversed if someone ceased to use benzodiazepines.

Taking benzodiazepines with other drugs increases the risks. Most notably, the risk of breathing becoming depressed.

 

Additionally, the effects of benzodiazepines may be masked if taken with a stimulant. This can lead to overdose if the user consumes more benzodiazepines due to not initially being able to feel the effects.

 

Certain medications (e.g. some antidepressants) may also interact with benzodiazepines to increase sedative effects.

One-off or occasional use of benzodiazepines is unlikely to result in the development of dependence. However, taking benzodiazepines regularly over a sustained period can cause very serious physical and psychological addiction. In fact, doctors are advised not to prescribe benzodiazepines for more than 4 weeks at a time.

People who become dependent on benzodiazepines may become tolerant to the drug’s effects, leading them to take increasingly higher doses. Dependency also leads people to experience withdrawal symptoms which include nausea, confusion, headaches, anxiety, and dizziness. Users may crave the drug and feel unable to cope without it. The longer the drugs are taken, the higher and more regular the dose and the stronger the benzodiazepines, the higher the risk of developing a dependence.

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

Long term use of benzodiazepines is often accompanied with the use of other drugs, such as alcohol and opioids. This is because some users may feel that benzodiazepines enhance the effects of a drug, or lessen the effects of drug withdrawal/comedown, or both. Those who solely use benzodiazepines outside of medical use often do so after becoming dependent on them having been prescribed them by a doctor.

Acute withdrawal effects for some benzodiazepines can be severe, although for many they will be milder. Acute withdrawal effects include anxiety, increased heart rate and blood pressure, shaking, insomnia and sensitivity to sound/light. Very severe withdrawal can cause symptoms that require intensive care, such as seizures. Someone who has been taking a benzodiazepine regularly for a sustained period should stop under the supervision and guidance of a doctor. Abruptly stopping use can be harmful so it is often better to taper use gradually before stopping entirely. To do this safely, professional advice is recommended.

Potential effects of long-term benzodiazepine use include anxiety, depression, and insomnia. These effects may last for months, depending on how dependent a person was on the drug, which drug was used, the length of time used, untreated on-going psychiatric conditions, as well as other personal factors such as why the drug was initially prescribed or used illicitly.

There are possible harms of long-term benzodiazepine use, although not everyone experiences problems with long term use. Specific harms that could be caused by long term benzodiazepine use include lack of energy, sleep problems, impaired memory, and changes in personality (becoming more aggressive, for example). Long term benzodiazepine use is also associated with anxiety related mental health problems such as panic disorder or social phobia. This may be because long term use causes the brain and body become reliant on the drug’s anxiety-relieving effects. It may therefore be particularly risky for people with depression/anxiety disorders to take benzodiazepines long term.

There is some evidence suggesting that long-term benzodiazepine use may increase the risk of dementia. However, other experts think that the evidence of this is not yet convincing.

How much are you taking, how often?

The occasional medical or recreational use of benzodiazepines has a relatively low risk of harm. However, benzodiazepine dependence and withdrawal can develop after a few weeks of use and can cause considerable harm to quality of life and health. If you develop tolerance to any of the effects of a benzodiazepine, this should be taken as a warning sign that the drug may be harmfully affecting your body and brain.

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

Drug effects are unpredictable, but mixing drugs makes the effects on your body and mind even harder to control. Deaths involving benzodiazepines generally involve other drugs too. It is particularly dangerous to combine a benzodiazepine with another drug that can depress breathing such as alcohol, heroin (or any opioid) or GHB. Additionally, if someone is taking antidepressants or even antihistamines, these may increase the effect of the benzodiazepines. Grapefruit juice can do the same with a few types of benzodiazepine. You should check whether this is possible if taking a benzodiazepine.

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Alkyl nitrites, commonly known as ‘poppers’, are liquid compounds which cause a headrush and smooth muscle relaxation when their vapour is inhaled. Amyl nitrite, the first alkyl nitrite to be developed, was synthesised in 1844 and was used from 1867 to help relieve angina (chest pains). Widespread recreational use of amyl nitrite is thought to have started in the 1960s. After consequent restrictions on its production and use, various other related alkyl nitrites were developed. The main examples include isopropyl nitrite, isobutyl nitrite and butyl nitrite.

Poppers come in liquid form in small bottles, often with colourful wrappers. The contents evaporate into a breathable vapour at room temperature. They are often sold labelled as ‘room odourisers’ as it is illegal to sell them for human consumption.

The vapour can be inhaled into the nose or mouth directly from the bottle. If the liquid comes into contact with skin, this can cause a crusty rash to form. Contact with the nose and lips is a particular concern, as these areas may touch the rim of the bottle when vapour is being inhaled.

Some users dip the end of a cigarette into the liquid and use it to inhale the vapour without lighting it. The cigarette should not be lit after this, as it becomes dangerously flammable. This method could be risky if any of the liquid, rather than just its vapour, is breathed into the lungs.
Some users transfer a small amount of liquid onto a cloth, cotton wool or paper, and put this into another sealable bottle or container. The vapour is then inhaled from that container. This may minimise the risk of accidental skin contact with the liquid.

If poppers liquid is ever swallowed or aspirated, medical help must be sought immediately.

The exact mechanism of how alkyl nitrites work in the body to produce their effects is unknown. However, some of the effects experienced can be attributed to the relaxing of smooth muscle that poppers induce.

The loosening of smooth muscle surrounding blood vessels is why poppers cause a drop in blood pressure. The effect on blood pressure and blood vessels in the brain may be what causes some of the effects of poppers: light-headedness, dizziness, and thumping sensations in the head. However, it is not known which effects of poppers are due to direct effects on the drug in the brain and which effects are due to the drop in blood pressure.

Amyl nitrite was originally used to treat angina, where poor blood flow to the heart causes pain. Poppers can alleviate angina by relaxing narrowed blood vessels, although now other more reliable medications are used for this, such as isosorbide dinitrate or nitro-glycerine, a chemical better known as an explosive.

Amyl nitrite is used in some countries for the treatment of cyanide poisoning.

Amyl nitrite may under rare circumstances be recommended to patients who engage in the risky sexual practice of asphyxiation, which kills more than 500 men in the United States per year. Poppers in this case serve as a harm reduction strategy; whilst not totally safe they offer a similar experience with lower risks of death.

When the vapour of poppers is inhaled, it very quickly enters the bloodstream via the mouth, throat and lungs, causing intense but short-lasting effects, typically 2-5 minutes.

The ‘high’ can be described as a dizzying head rush, which can be euphoric, often accompanied with sensations of warmth and sometimes a thumping feeling in the head. The drug may also make the skin flush.

Anecdotal reports state that poppers enhance sexual experiences by increasing intensity and lengthening orgasms. Users report that poppers create feelings of wellbeing and increase sex drive. It is also used to facilitate sex because it relaxes muscles in the anus and vagina. However, some people have also reported problems getting or maintaining an erection when using poppers.

The most common after-effect of the drug is headaches. Some have reported feeling nauseous after using poppers, and people may also feel very dizzy and can faint.

The risks of using poppers for healthy people are relatively low. However, there are still associated risks to be aware of.

Using poppers can lead to methemoglobinemia when an overdose is taken. Methemoglobinemia occurs when haemoglobin, which transports oxygen in the blood, is converted to methaemoglobin, which binds to oxygen but does not then release it to cells in the body. Severe methemoglobinemia leads to oxygen starvation. This can potentially lead to organ failure, blindness, brain damage and in the most severe cases, death. Overdose of alkyl nitrites can occur easily through accidental swallowing. Inhaling poppers in very large quantities can also lead to overdose.

However, an overdose of alkyl nitrites is rare, suggesting that ordinary use should not put someone in danger of overdose.

If someone is continuously taking a lot of any alkyl nitrite and they experience shortness of breath, a lack of energy, tiredness, and bluish colouring of the skin, they may be developing methemoglobinemia and should seek urgent medical help. If someone swallows poppers, they must go to a hospital by ambulance immediately. As well as the poisoning risk, swallowing poppers results in throat irritation, nausea, and vomiting.

It has been suggested that the use of poppers can negatively affect eye health. However, more research must be conducted to confirm this link.

Some people who use poppers heavily have developed crusty skin lesions around the nose, mouth, and lips. Poppers can cause a chemical burn if the liquid comes into contact with the skin and should be washed off immediately. Contact with the eyes is very painful and requires prompt first aid of flushing with plenty of water. If discomfort continues, users should seek medical advice as soon as possible.

Poppers are also very flammable. Bottles of alkyl nitrite should never be heated or placed near an open flame. Burns could be obtained if a cigarette used to inhale poppers is later lit.

Poppers lower blood pressure and increase heart rate. It could be riskier for people with heart conditions or abnormal blood pressure. There could also be added risks for people with glaucoma or anaemia.

Poppers should not be mixed with other drugs.

Mixing poppers with drugs which affect blood pressure is particularly risky. This includes any blood pressure medication and erection-inducing drugs, such as sildenafil (Viagra). The interaction of poppers with such drugs can dangerously affect blood pressure and heart rate, and can lead to fainting, heart attack or stroke.

Poppers are not thought to be physically addictive.

After using poppers consistently to enhance sex, some people have reported feeling reliant on them in order to perform sexually. Avoiding the use of the drug for a while should allow for normal sexual response to return.

Care must be taken when using poppers to ensure that no skin contact occurs and that the liquid is kept away from open flames.

Under no circumstances should poppers liquid ever be swallowed, as this will lead to poisoning.

Poppers should not be mixed with other drugs, especially those which alter blood pressure.

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Alcohol is a chemical substance that can be found in alcoholic drinks, household products, fuel, and much more.

An alcoholic drink is one that contains ethanol, which is a form of alcohol that is produced by the fermentation of grains, fruits, or other types of sugar. When alcohol is consumed, it is a psychoactive drug that acts as a depressant for the central nervous system.

The 4 types of alcohol are isopropyl alcohol, methyl alcohol, undistilled ethanol, and distilled ethanol. Distilled ethanol and undistilled ethanol can be consumed.

Yeast or bacteria chemically convert sugars into ethanol through the process of fermentation. Sugars that are used to produce ethanol can come from barley, wheat, grapes, or other grains and fruits depending on the type of drink being created. Fermented beverages can be drunk directly, or can be further distilled to a higher alcohol percentage.

Examples of distilled ethanol include Vodka, gin, brandy, whiskey, rum, and tequila are some of the best-known distilled drinks, and typically have an ABV of around 40%.

Examples of undistilled ethanol include beer, wine, and cider, which typically have an ABV of no higher than 15%

On the other hand, both isopropyl and methyl alcohol should not be consumed.

Isopropyl alcohol is typically used for disinfection purposes.

Methyl alcohol typically is seen in things like paint, solvents, printing ink, etc

Alcohol has a few different functions in the brain. It represses an excitatory neurotransmitter, glutamate, and increases an inhibitory neurotransmitter, GABA. This means that one’s thoughts, movements, and speech are impaired, and become more impaired as consumption increases. Alcohol’s repressive effect as a nervous system depressant, means that it slows down parts of the brain. Areas that it affects include those that control inhibition, thought, perception, attention, judgement, memory, sleep and coordination.

However, alcohol also increases the release of the neurotransmitter dopamine, which is known for its role in the “reward system” of your brain. This causes your brain to think it is having a good time, and therefore one may continue to drink to chase the release of dopamine. However, with consistent exposure the effects of dopamine begin to diminish. At this point, one is often attached to the effects of dopamine so they continue to drink with the hopes of feeling the “high”, despite not receiving it.

Though different for everyone, depending on factors such as gender, size, metabolism, etc, alcohol can cause: memory loss, slurring of speech, impaired judgment, vomiting and nausea, sleepiness, breathing issues, loss of consciousness, issues with bladder and bowel control, and even coma or death. With long-term alcohol abuse, heart issues such as cardiomyopathy (stretching of heart muscles) or arrhythmias (irregular heart beats) can occur, as well as a multitude of liver issues.

The effects of alcohol on behaviour depend on the level of alcohol in the blood:

  • Low blood-alcohol-concentration will depress parts of the brain involved in inhibition, making the user more animated and social. It may also lift your mood, but even at low levels alcohol can still affect coordination and judgement. Alcohol in a social context often helps people to be happier and more confident. Tipsy people can be chatty and giggly, although some may become withdrawn. Alcohol often makes people say and do things they normally wouldn’t (reduces inhibitions). When people aren’t at bars, clubs and parties, many people consume alcohol for its calming effects, for example, wine with an evening meal. Many people say they enjoy alcoholic drinks for the taste, rather than using it as a drug. However, the taste of alcoholic drinks is usually unpleasant to people when they first try them and later enjoyment of the taste may be a learned association with the drug. After a couple of drinks, people start to lose the ability to concentrate and think straight.
  • Higher concentrations of alcohol will begin to seriously hamper coordination, memory and judgement. Alcohol also depresses the ability to regulate emotion, which is why intoxicated people can become emotional or aggressive.
  • Large enough concentrations of alcohol in the blood will cause users to become woozy and they may pass out. A potentially fatal concentration of alcohol in the blood will depress areas of the brain involved in breathing, causing breathing to slow dramatically and eventually stop.

Alcohol also causes the user to urinate more, causing dehydration. Following heavy use of alcohol the user may experience a ‘hangover’, which typically is experienced the morning after (although a hangover can last longer). Effects of a hangover can include: nausea and vomiting, headache, thirst, sensitivity to light and noise, diarrhoea, low mood and anxiety. People can generally be described as not being at their best on a hangover, and studies have found things like memory to be worse during a hangover.

Alcohol at high concentrations is quite toxic, which makes it useful for killing germs. Alcoholic hand gels and wipes are an essential means of preventing infection, and mouthwashes often use alcohol too. However, drinking alcohol doesn’t work to cure infectious diseases.

It has been suggested that alcohol in moderation could have some health benefits (see alcohol myths and misunderstandings below). However, any suggested health benefits are outweighed by the potential damage to your health.

Historically, alcohol was used to stupefy people before having painful operations such as getting their teeth pulled out. Ethanol has also been used as an antidote to poisoning by methanol, a more toxic alcohol chemical which causes blindness and death.

There are many risks associated with drinking alcohol, both at time of consumption and over time. Alcohol consumption not only causes an increased risk of a multitude of health issues, but the effects of alcohol can also be seen in an increase in violence (such as suicide, homicide, or sexual assault), or injuries (falls, drownings, vehicle accidents). Amongst the most common injuries are those associated with accidents caused by drunk drivers.

Over time, excessive alcohol use can lead to a variety of heart issues, an increase in the likelihood of cancer, memory and learning issues, an increase in severe mental health issues, and a weakening of the immune system.

Most risks associated with drinking alcohol can be avoided by not consuming copious amounts and not drinking on a frequent basis.

Alcohol causes and worsens many health conditions, especially when consumed frequently and/or in large amounts. If you have high blood pressure, cardiovascular disease, liver conditions, conditions that make you bleed easily, mental health issues, or any other serious health problems, alcohol may cause you greater harm than it does the average person. If you are concerned, always discuss alcohol consumption with your doctor to better understand how it would impact you specifically.

Drinking whilst pregnant can cause harm to the foetus, particularly when alcohol is consumed in the beginning of the pregnancy. This is known as foetal alcohol syndrome and can cause brain damage, growth issues, or facial abnormalities.

Consuming alcohol with any other drugs increases the risks of unpredictable consequences. Drinking alcohol and consuming depressants such as Valium or Xanax can cause dizziness, stumbling, memory loss, and even death. Drinking and consuming stimulants such as Adderall, can hide the impacts of alcohol which makes it harder for people to gauge their intoxication levels, often resulting in overconsumption. Drinking in combination with taking opiates such as Percocets or OxyContin can cause a decrease in blood pressure and pulse, loss of consciousness, slowed breathing, coma, or even death.

Drinking and smoking are often closely linked, with a large portion of patients diagnosed with dependence on one diagnosed with dependence on the other. The frequent use of alcohol and tobacco causes a significant increase in the risk of cancers (particularly moth or oesophageal cancer), and cardiovascular diseases.

Many medical drugs have side-effects when taken with alcohol. Others may not work effectively. Always read the leaflet or check with your doctor.

Alcohol dependence, often called alcoholism, is common. Dependence on alcohol means that the user has lost some or all control over their use of alcohol and are likely to suffer withdrawal effects if they don’t drink. This is more common in men, although women who are alcohol dependent usually suffer more severe harms as a result of alcoholism.

Not everyone who drinks alcohol is equally at risk of becoming dependent. Drinking from an early age and using alcohol as a tool to blot out stress and anxiety are just some factors associated with drinking too much and becoming dependent. Alcoholism can run in families, due to both genetic reasons and the influences people are exposed to. Traumatic experiences in early life, such as abuse, increase the chances of becoming alcohol dependent.

Being addicted to alcohol (alcoholism, alcohol dependence) makes people particularly vulnerable to the many health harms that alcohol can cause. Addiction changes a person’s priorities, which can be devastatingly disruptive to the lives and wellbeing of the addicted person and their families. People who are worried about alcohol addiction can get help and support by visiting their doctor.

Mildly addicted people suffer psychologically when they try quitting and may get cravings and feel anxious and miserable without drinking. People who are suffering from alcohol dependence become physically as well as psychologically reliant on alcohol. Physical reliance on alcohol means that a person’s body has adapted to having alcohol in it, and so removing the alcohol causes physical withdrawal symptoms. Quitting can cause flu-like or hangover-like withdrawal symptoms for about 3 days. Withdrawal from more severe alcoholism can have dangerous consequences, especially episodes of delirium tremens, which is potentially fatal. This includes shaking, hallucinations and a racing heart.

Withdrawal for severe alcohol addiction should only be attempted with medical help.

Health harms

Regardless of addiction status, drinking large amounts of alcohol increases the risk of a variety of diseases. The harms of drinking large quantities of alcohol are associated with other issues, such as a bad diet, depression, and social problems. Alcohol damages the heart, pancreas and other vital organs. The liver, which plays a large role in the body’s detoxification from alcohol, often sees the worst effects of alcohol usage.

Alcohol is a carcinogen, meaning that it is capable of causing cancer. Alcohol can also cause other issues such as diabetes, hormonal imbalances and even sexual dysfunction.

Alcohol is particularly toxic to the brain. In adults, alcoholism causes brain shrinkage. Excessive use in older ages increases the risks of developing Alzheimer’s. Long-term alcoholism coupled with malnourishment can cause Wernicke–Korsakoff syndrome, which can leave permanent brain damage with dementia and amnesia (inability to remember).

Many people with alcohol dependence also suffer from mental illnesses. Mental illnesses may increase the risk of developing alcohol dependence, just as alcohol dependence may increase the risk of developing a mental illness. Some people may drink as a result of their mental illness, while others could develop a mental illness as a result of their alcohol dependence. Often, mental illness and alcohol dependence can be thought of as co-occurring conditions, which is when the conditions occur simultaneously. Co-occurring conditions tend to aggravate each other. When one issue is ignored, the other often worsens.

 

Damage to employment, families and communities

Unhealthy relationships with alcohol often impact others. Addictions make it more difficult to hold down a job and can be damaging to relationships. Alcoholism, like any addiction, takes up time and resources, making it very difficult for homeless and vulnerable-housed people to improve their situation.

 

Association with crime and antisocial behaviour

When people are under the influence of alcohol, they are less able to act with good judgment or control violent impulses. The majority of assaults on young people that lead to hospitalization are related to alcohol consumption, and roughly half of domestic violence occurs after the perpetrator has been drinking. Drunkenness, even when non-violent, uses up police time, accounting for most arrests that occur at night. Very drunk offenders are particularly time-consuming, as they are more likely to be disruptive and uncooperative, and require supervision to ensure their safety.

Being aware and in control of what you are drinking is very important to reducing the harmful potential of alcohol. If you know and are aware of what drinks you’ve consumed, it is easier to manage your intake. If you are also drinking water or other hydrating drinks in addition to the alcoholic drinks, it aids your body in the alcohol detoxification process and helps to maintain your mental capacity. It is also important to know your tolerance level.

Always have alternative transportation options if there is a chance that you might be consuming alcohol. Driving with any alcohol in your system poses risk to not only yourself, but your passengers and other drivers. You can designate a driver, or call a car ride service such as a taxi.

It is important to recognize not only how much you drink, but also how frequently you drink. The NHS states that the recommended weekly limit is 14 units

Loss of consciousness is often a result of consuming large amounts of alcohol. If one loses consciousness, they run the risk of throwing up and potentially choking on their vomit. To avoid this, ensure that the person is lying on their side so that their airway is not blocked. Continue to monitor the person and if they become unresponsive, vomit while unconscious, or have slow breathing, make sure to call emergency services.

Does drinking water cancel out the effects of alcohol?

Drinking water does not protect your liver and other organs from the harm of processing alcohol, but it may help someone in their pace of alcohol consumption. Pacing alcohol consumption makes it less likely that you accidentally consume more than intended. Drinking water also helps to curb dehydration caused by alcohol.

 

Is tolerance to alcohol a good thing?

Tolerance to alcohol is often thought of socially as something positive or indicative of toughness. However, high tolerance levels means that someone will get less drunk, making them likely to drink larger amounts. Large amounts of alcohol make them more at risk of harms like liver disease and alcohol addiction. Tolerance to alcohol also runs in families, which is one of the reasons why alcohol addiction runs in families.

 

Does consuming different types of alcohol make you more drunk?

Mixing drinks can make you feel sick or nauseous. However, drinking different types of alcohol makes it more difficult to gage your intake levels, as different drinks have different ABV levels. Alcohol is often paired with sugary drinks. Both alcohol and sugar cause dehydration and strain to the liver.

 

Does coffee sober you up?

Caffeine may make a drunk person less sleepy and more alert but it does not have the capability to neutralize the alcohol in your system. Drinking coffee to perk yourself up before doing something you would not do drunk (like driving) is a bad idea. Using caffeine-containing energy drinks to keep you going increases the strain on your heart as both caffeine and alcohol have negative cardiovascular effects.

 

Is alcohol in moderation good for you?

iThere is a common misconception that alcohol, ‘in moderation’, has proven health benefits. In fact, most of the total number of deaths and diseases caused by alcohol happen to people in the large majority of the population who are ‘moderate’ drinkers, not in the minority who are heavy drinkers. No-one should justify their alcohol consumption with the belief that they are benefiting their health.

There is some controversy and contested evidence about whether light drinking could be protective against specific conditions, like heart disease in middle age. A controlled trial, the only kind of study which could demonstrate this for certain, is impossible. Some observations at the population level (epidemiological research) seem to show that the middle-aged people who are the least likely to die from heart disease are not those who never drink, but those who drink very little. However, this evidence is not enough to prove that drinking a little makes you more healthy than not drinking. Some non-drinkers in the samples may never drink because they have health problems, or because they quit drinking after it harmed their health. The intake of alcohol which appears to be associated with the smallest chance of illness and death is very low, around half a pint of beer or half a glass of wine. Increased harm is observable at levels not much higher than this.

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.