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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Short-term physiological effects include:

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

Possible long-term physiological effects:

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

Possible adverse psychological reactions:

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

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

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

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

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

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

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

Alcohol and Adderall

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

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

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

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

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


It is only a stiff cup of coffee.

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


It makes you smarter.

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


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

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

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chemical structure/skeleton of modafinil molecule

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

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

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

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

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

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

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

Physiologically, modafinil increases blood pressure and resting heart rate.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Mental Health

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


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

Oral Contraception

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


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


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


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

‘It can make you smarter’

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

• Taking it with other drugs increases the risks

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

• You may overheat when taking the drug

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

• Tolerance is a bad sign

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

Is it actually plant food or bath salts?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Currently, MDMA has no medical uses.

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

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

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

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

Many people feel depressed in the days after taking MDMA.

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

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

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

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

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

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

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

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

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

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

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

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

How much are you taking?

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

Do you know what you are actually taking?

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

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

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

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

Does MDMA put holes in your brain?

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

Is MDMA (ecstasy) powder purer than ecstasy pills?

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

Does MDMA (ecstasy) drain your spinal fluid?

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

Does MDMA (ecstasy) cause Parkinson’s disease?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Cocaine comes in different forms with distinct risks attached.

Powder cocaine (hydrochloride)- usually snorted

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

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

Crack cocaine- usually smoked

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

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

Coca leaves

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

What are you taking and how?

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

Could you get addicted?

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

Are you considering the harms cocaine can cause to others?

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

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

Is cocaine a great drug for sex?

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

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

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

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

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Caffeine (1, 3, 7- trimethylxanthine) is a toxin that some plants produce to defend themselves. Small amounts are not harmful to humans, but have stimulant effects, making users feel more alert and energised. Typical use of the drug comes from caffeinated drinks such as coffee and tea, and also soft drinks such as cola and ‘energy drinks’.

Like other stimulant drugs such as cocaine, caffeine in high enough doses can harm and kill. However caffeine use is very much safer and more manageable than the use of cocaine and other potent stimulants, and only exceptionally rarely causes serious harm.

Caffeinated drinks (generally low risks of harm).

Caffeine is found in drinks like coffee, tea, and mate (a tea drunk in Argentina). Caffeine can also be found in ‘energy drinks’ which have high caffeine content, and some soft drinks. In Europe, drinks (not based on coffee or tea) with a caffeine content of more than 150 mg per litre, have to be labelled as high caffeine content with the amount of caffeine on it.

Shops also sell caffeine shots, which are small amounts of sugary drink with a high caffeine content. Like alcohol shots, it is easy to drink a lot of these quickly before realising you have had too much.

It is common to become addicted to caffeinated drinks, in that stopping use will lead to withdrawal symptoms, although most people would not find it difficult to stop caffeine use.

Caffeine is often listed as a flavouring on soft drinks, although it may not be the case that caffeine adds to the taste of the drink, rather it increases the desire to consume it.

Caffeine tablets (low risk if used according to directions, potential for overdose if misused)

Caffeine tablets are legal and are used to increase alertness. Some beliefs about their effectiveness, for example in improving exam performance, are not wholly supported by the evidence. They do not replace the need for sleep, in fact a nap can be much more beneficial.

Caffeine as an adulterant in illegal drugs (could sometimes be harmful)

Analysis of drug samples show that caffeine is commonly added, which adds bulk cheaply and so increases the dealers’ profits. Caffeine has been identified in heroin, where it may make the drug easier to smoke. It is commonly added to stimulant drugs like cocaine, amphetamine (speed) and MDMA (ecstasy) where its stimulant effects may disguise how impure the drug is, and may also increase the risks.

Caffeine hinders the action of the adenosine. Adenosine dampens down brain activity, so by getting in its way (competitive inhibition) caffeine stimulates many circuits in the brain.

Caffeine also works because we have powerful beliefs about its properties. If you consume caffeine without believing something like “I’m consuming caffeine which will make me more alert”, the caffeine may not increase your alertness at all.

Caffeine has stimulant effects and makes people more alert, reducing feelings of tiredness. It is widely believed to improve mental performance but the evidence for this is mixed.It has been suggested that the appearance of performance enhancement is because caffeine reverses withdrawal effects in regular users rather than improving overall mental ability. In people who are not regular users, any improvement is likely to be counteracted by anxiety and jitteriness which make it difficult to focus. Caffeine may in some circumstances increase a feeling of alertness whilst actually decreasing ability.

Caffeine causes sweating and also makes people urinate more, although tolerance to this effect develops quickly so people who, for example, drink coffee every morning usually do not find this to be a problem. Caffeine can also lead to difficulty sleeping (insomnia).

Some people become anxious or irritable after caffeine. Unpleasant feelings become more likely the higher the amount you consume.

Caffeine has a few medical uses. Its stimulant properties mean it is sometimes useful to keep premature babies breathing.

Caffeine is also an ingredient in common over the counter medications for flu, colds and headaches. It can sometimes make pain relief drugs work more quickly and effectively, and can counteract the drowsiness caused by some drugs. Caffeine does not treat colds, but can relieve the symptoms of sluggishness that often come with them.

Low or moderate caffeine consumption has minimal risks.

Caffeine can cause insomnia so people often avoid it in the evenings so that they can sleep properly. The half-life of caffeine is around 5 hours, meaning that after a cup of coffee at 6pm, an individual will still have half the caffeine left in their body at 11pm, and a quarter at 4am, disrupting sleep. Individuals vary in their reaction to caffeine, so the half-life could be much longer or shorter than 5 hours.

Regular high intake of caffeine is thought to cause behavioural changes including restlessness and anxiety/nervousness. It may increase the frequency of headaches in some.

Very excessive caffeine consumption can be harmful and even fatal. Most people who suffer harm after consuming caffeine have taken excessive numbers of caffeine tablets, or consumed excessive quantities of highly caffeinated energy drinks, sometimes mixed with alcohol.

Taking too much caffeine results in symptoms similar to taking too much of a stimulant drug, with overdoses causing anxiety/agitation, convulsions, tremors and hallucinations. People admitted to hospital after taking large amounts of caffeine typically have tachycardia (fast heart beat) and hypertension (high blood pressure). Additionally, a common feature of caffeine overdose is vomiting, which can be very severe. Other gastrointestinal problems such as diarrhoea and stomach pains have also been reported. People have died from caffeine overdose, and some deaths have been associated with high caffeine content energy drinks.

Excessive use of energy drinks, especially with exercise, could be riskier for some people with heart problems.

People who suffer headaches and migraines might benefit from exploring the role of caffeine in these. Whilst caffeine is a useful component in some headache pills, both the drug itself and caffeine withdrawal could be triggers for headaches.

Caffeine can worsen symptoms in people who easily become anxious.

Mental health issues such as schizophrenia and bipolar disorder, even if they seem in remission, may be worsened by very excessive amounts of caffeine. The drug may bring on episodes of psychosis or suicidality.

Caffeine seems to increase harmful effects of MDMA and other psychostimulants (amphetamine, cocaine) in raising body temperature, lowering the seizure threshold and harmful effects on the heart. This is problematic as many illegally sold drugs may contain some caffeine, and people taking psychostimulant drugs may also have consumed caffeine.

It has been suggested that drinking energy drinks with alcohol makes people more prone to risky behaviour.This may be because caffeine makes people feel less drunk from alcohol, whilst not improving thing like coordination or judgement.

Caffeine is a mildly addictive drug, tolerance to the drug does develop and people have reported withdrawal symptoms of: headache, tiredness/drowsiness, insomnia, stomach and joint pains and trouble concentrating. Caffeine withdrawal symptoms may be quite mild for most regular tea or coffee drinkers, who would most likely just get a bit irritable and headachy if they miss their morning cup.

Regular caffeine intake is not usually harmful and may even have some mildly beneficial effects.

Studies have suggested that habitual consumption of caffeinated drinks may have a small protective effect against certain forms of cancer. Further research is needed. Additionally, one study found that coffee consumption (not decaf) is linked with a lower chance of depression in women.
More research is needed to confirm any beneficial uses of caffeine, and it is possible that other things in tea and coffee, or different lifestyles of their users, may play a part in these findings.

For regular use, any beneficial effects of caffeine in energy drinks or colas would be outweighed by harm of the sugar.

As long as users recognise that caffeine is a drug and could be harmful in excessive amounts, caffeine poses a negligible risk to health.

How much are you taking?

Moderate caffeine use is not thought to be harmful, and may even be beneficial. Consumption of drinks like coffee or tea probably could not result in a caffeine overdose. Some ‘energy drinks’ can have very high caffeine contents, and should be used in moderation. Caffeine pills also may contain large amounts of caffeine (some contain up to 200mg of caffeine, which is like 4 cups of coffee). Check the label of energy drinks and tablets to judge how much caffeine you are taking.

Be aware that ‘legal highs’ and controlled drugs often contain caffeine. This is a problem as you do not know how much caffeine you are taking, and it could also increase the harms of some. One study of 6 ‘legal high’ products found that some contained around 90% caffeine. This means that taking one gram of the product would be like taking around 13 litres of cola, 3.75 litres of energy drink, or 12-15 cups of coffee.

You always need sleep

Caffeine improves some mental abilities in tired people, and many people use it to remain alert when they are tired. Caffeine is no substitute for sleep however, and not sleeping is harmful both psychologically and physically. Once the caffeine has worn off you are likely to ‘crash’ if you are very tired.


Being addicted to caffeine does not usually affect people’s lives for the worse. It does however mean that you can get withdrawal effects if you don’t have caffeine, which can be unpleasant. This would be worse for those who regularly have very large amounts of caffeine (which is easier to do with energy drinks and caffeine pills). A regular caffeine habit means that you are not necessarily making yourself more energised and alert than someone who doesn’t use caffeine, rather you need caffeine to maintain normal levels of energy and alertness. Frequent headaches can be related to caffeine withdrawal.

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Amphetamine comes in a variety of forms and varies in its purity.

Amphetamine sulphate

This is most common form of street amphetamine. It sometimes appears as a white, off white, sometimes pinkish crystal powder. This can be snorted, rubbed on the gums, dissolved in a drink or swallowed (wrapped in a cigarette paper). People may also dissolve it in water and inject it to produce a more powerful high. Injecting drugs carries particularly high risks of overdose, infections, addiction and damage to veins.

Amphetamine ‘base’

In Europe this usually refers to a putty or paste containing amphetamine sulphate. The name is confusing, because amphetamine can occasionally be found in its ‘freebase’ chemical form, an oily liquid, but this is not what is usually meant by ‘base’. So-called base amphetamine is often much stronger than the normal powder kind, although the purity of illegally produced amphetamine is so variable that you never really know.

Amphetamine pills

These come in various colours, shapes and markings. Sometimes pills sold as MDMA (ecstasy) or other drugs may actually contain amphetamine. As with the forms above, purity is variable and often low, with much of the pill being other substances which could themselves be harmful.

Prescription amphetamines

There are a range of prescription drugs containing amphetamine, related to amphetamine, or which are turned into amphetamine by the body. These are used to treat conditions such as ADHD or narcolepsy but have been known to end up being used recreationally.

Amphetamine is a psychostimulant. This means that it works by increasing the activity in certain parts of the nervous system. Specifically, amphetamine increases the amount of dopamine, noradrenalin and serotonin in areas of the nervous system such as those involved in reward/pleasure, movement and thought/decision making (amongst others). The effects that amphetamine can have are both physical (e.g. increased heart rate) and psychological (e.g. increased confidence). Many other drugs are variations of the amphetamine molecule.

When swallowed the effects of amphetamine normally appear in around half an hour. This may be longer if someone has a full stomach. Snorting amphetamine usually produces effects in only a few minutes, and injecting amphetamine will cause effects almost instantly. The effects typically last for 4-8 hours, although the after-effects can last for several days.

Possible psychological effects of amphetamine include increased confidence, feelings of wellbeing, alertness, focus, and motivation. People using amphetamine will often become more chatty, sociable and may experience increased sex drive. If the drug enters the body quickly (especially through snorting or injecting) then it may also cause a ‘rushing’ euphoric feeling, which lasts for a short period of time.

The energising effects of amphetamine can reduce feelings of tiredness and have often been used by people who want to do something active, like dance, for long periods of time. As amphetamine can increase energy levels, motivation and focus, it has also been used as a performance enhancer. For instance, some people use amphetamine (often in the form of medications meant to treat ADHD) as a study aid to help them focus and work for long periods of time.

Potential undesirable effects include increased anxiety, irritability, aggression, restlessness and paranoia. Psychotic symptoms (like those suffered by people with schizophrenia) can occur when taking amphetamines. These can include paranoid thoughts or delusions, for example believing that people are spying on you or recording your movements, and/or hallucinations, for example hearing people talking about you or hearing music and noises that are not really there. Psychotic symptoms may happen during amphetamine intoxication and can last days or weeks after the intoxication phase of drug use.

Some people have become violent after taking amphetamine. Physical effects of amphetamine include: increased heart rates and constriction of blood vessels (higher blood pressure), increased energy, dilated pupils, a rise in body temperature, reduced appetite, and dry mouth.

The ‘comedown’ period after amphetamine use can last for a few days. People can feel tired, muddled, depressed, socially incapable, irritable, and anxious. Additionally people may experience insomnia and restlessness, twitching, muscle aches, and fluctuating temperature. At very high doses the after-effects can be severe, including vomiting, diarrhoea, and a psychosis similar to schizophrenia.

Medications that contain amphetamine, or related drugs, are used to treat attention deficit-hyperactivity disorder (ADHD). At the right dose, such medications can help some people focus.

Amphetamine and its derivatives are sometimes used to treat symptoms of narcolepsy, a condition where people become very sleepy and fall asleep at inappropriate times.

Amphetamine/amphetamine like drugs may have potential uses as a last resort for treating depression, especially where people may have low energy and motivation. However, amphetamine’s potential for addiction and harm is considerable, so conventional antidepressants will almost always be more appropriate.

It is uncommon for people to die from an amphetamine overdose, although in some cases people have died from amphetamine induced strokes or heart attacks. This is because amphetamine raises blood pressure and constricts blood vessels. People at risk of heart disease or strokes are more likely to experience such complications from taking amphetamine.

Amphetamine in very large amounts can cause amphetamine psychosis and can make people paranoid, delusional and hallucinate. Some people have violently harmed themselves or others in a state of amphetamine psychosis. Additionally, some people have failed to fully recover from amphetamine psychosis and have had lasting symptoms. People taking amphetamine with a history (or family history) of mental health problems are more likely to develop amphetamine related mental health problems.

Some people may inject amphetamine, which carries much higher risks including the chance of getting HIV, hepatitis, or bacterial infections. If you choose to inject despite the added dangers, the risks can be reduced by using new needles and injecting equipment. You can get these from needle exchanges, which may be found in pharmacies or hospitals.

Yes. Amphetamine is potentially more risky for people who have or are at risk of heart or circulation problems including high blood pressure.

Amphetamines may worsen glaucoma due to changes it can have on blood pressure.

Additionally, amphetamine may be riskier for people with mental health problems. People with schizophrenia or a history of psychosis should avoid taking amphetamines as they are usually much more sensitive to getting psychotic side-effects, and could trigger a relapse of schizophrenia or psychosis.

Taking amphetamine with other stimulants such as MDMA can result in very high blood pressure or body temperature. Amphetamines may also mask the effects or early warning signs of depressant drugs such as alcohol or heroin, allowing the user to accidentally overdose.

Amphetamine can be very dangerous if you have taken certain medications, for example some antidepressants (MAOI inhibitors).

Amphetamine has a fairly high potential for addiction. Regular use of amphetamine is likely to lead to physical and psychological dependence on the drug. Habitual amphetamine use can become increasingly compulsive and out of control and users may experience withdrawal symptoms without it. Withdrawal symptoms are generally a rebound from the drug’s physical and mental effects, so for amphetamine symptoms include: tiredness, hunger, irritability, and depression. Additionally amphetamine withdrawal can cause insomnia, mood swings, and cravings for the drug.

Long-term use of amphetamines can cause very serious physical harm and devastate quality of life. The heart can be damaged, and heart-beat can become irregular. Long-term amphetamine use is associated with anhedonia; a general difficulty in finding pleasure in life without the drug, which may persist for some time after quitting the drug. It has also been associated with differences in the structure of the brain. From the available evidence it is difficult to establish to what extent brain differences and anhedonia are reasons that people become amphetamine dependant, or consequences of heavy amphetamine use. However, the second possibility should be taken seriously. The negative effects of long term use of amphetamines may be intertwined with the harms of adulterants in the amphetamine, and of poverty and chaotic lifestyles. Amphetamine dependant people often suffer from serious problems sleeping, poor nutrition and anorexia (from reduced hunger) and a resulting appearance of accelerated aging.

>Being careful what, and how much, you are taking

Amphetamine varies in strength and there have been spates of overdoses associated with strong batches, including so-called ‘base’ amphetamine (which is rarely ‘base’ in the chemical sense). Most ‘amphetamine’ available on the unregulated, illicit market contains more adulterants, fillers and other drugs than actual amphetamine. It may contain no amphetamine sulphate at all, as some other drugs mimic amphetamine’s effects. These mimics might be more harmful. If you take it despite the risks, it is a good idea to try a small amount of the drug to see what it does and wait for the effects to peak before considering if you want more. Even if the amphetamine is pure, higher doses have greater risks.

Injecting drugs tends to be much more harmful

It is much easier to take too much amphetamine when injecting. Also, injecting carries a whole range of extra risks including infection and damage to veins.

Tolerance is a warning sign

If a person is taking amphetamine regularly they may develop tolerance. Requiring more of the drug to achieve the same effects suggests that the use of amphetamine is causing lingering changes in brain chemistry. Increasing tolerance is often a signpost on the transition between recreational and dependent drug use.

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Tobacco was brought to Europe from the Americas five centuries ago. It is now considered the world’s single biggest cause of preventable death.

Tobacco is the herb Nicotiana tabacum. The plant makes the toxic substance nicotine as a chemical defence to stop insects eating it. It is possible that other chemicals in tobacco smoke may add to nicotine’s addictive effects (by disrupting the enzyme monoamine oxidase A).

By far the most popular and the most harmful way of consuming nicotine from tobacco is by smoking it. Smoking also seems to be the most addictive way of consuming nicotine, with fewer smokers being able to quit than people who use nicotine in other ways.

Smoking Cigarettes

Cigarettes are made of fermented, processed and dried tobacco leaves and stems (with some additives). Smoking them allows the nicotine to be absorbed into the blood through the lungs. Blood carrying nicotine reaches the brain within seconds, producing the mental effects smokers are after and satisfying nicotine craving in addicts. Unfortunately, as tobacco leaves burns, hundreds of harmful chemicals are created or released which are also drawn into the lungs. Half of the people who do not quit will die of a smoking-related disease. Smoke also drifts around, harming other people.

Cigars and Pipes

Cigars and pipes are alternative traditional ways of smoking. Some smokers of these do not inhale the smoke deeply into the lungs, but only draw it into the mouth. This causes less damage than cigarette smoking, although such smokers are still harmed by smoking. If users do inhale fully, the harms are likely to be similar to the harms of a similar amount of cigarette smoking.

Hookah pipes (shisha)

A hookah or hubble-bubble is a sort of tobacco pipe where smoke is drawn through a bottle of water. The tobacco (shisha) is flavoured and sweetened. People who smoke hookah regularly also have an increased chance of smoking related diseases such as lung cancer.

Smoke-free tobacco and other nicotine-containing products

Some forms of tobacco are not smoked, which prevents many, but not all of the harms of smoking. They confine the harm to the user, whereas smoking can harm others. Chewing or dipping tobacco, and snus (snus is illegal to sell in most of Europe) are products which release their nicotine into the mouth. The nicotine fix is achieved with less of the cancer-causing chemicals produced by burning and without the damage smoke causes to the lungs. Snuff is a powdered tobacco product which is inhaled up the nose, often making you sneeze. Whilst it increases the cancer risk for the places it contacts, the nose, mouth and throat, the overall level of risk of harm and death is also lower than with smoking cigarettes.

In the last few years, there have been more products invented that contain nicotine extracted from tobacco. Lozenges, chewing gum and skin patches deliver doses of nicotine with a fraction of the harms associated with smoking. They are mostly used as ‘nicotine replacement therapies’ to help people wean themselves off cigarettes and eventually quit the drug entirely.

Use of ‘electronic cigarettes’ is growing. These deliver a puff of vaporised liquid containing nicotine, which simulates smoking without burning. They have not been researched thoroughly, but it is very likely that they are much less harmful than actual cigarettes because they do not produce the range of damaging chemicals found in tobacco smoke, although they are not entirely harmless. It is still a matter of scientific and political controversy whether e-cigarettes and other alternatives to cigarettes can offer benefits to the health of society.

Because of its position in our culture, tobacco and the nicotine it contains is often not considered a mind-altering drug. In fact, nicotine affects the brain in several different ways and changes it over the long-term. Nicotine acts to increase the production of other chemicals in the brain known as neurotransmitters that affect brain function.  By causing the release of noradrenaline nicotine acts as a stimulant that produces a slight buzz. It is thought to cause improved focus by increasing acetylcholine, whilst its action in increasing beta-endorphin production relieves anxiety, giving nicotine some calming effects as well as stimulating effects. Nicotine also produces long-term effects on the dopamine system, which is involved in reward, mood and addiction.


Smoking is a very different experience depending on whether  you are a smoker or non-smoker.

To a non-smoker, smoking can give a pleasant light-headed buzz, but smoke inhalation may be uncomfortable or painful, causing coughing, and making the user feel weak, dizzy and sick. Everyone responds to drugs differently; it seems that some people find their first cigarette revolting, and some find it rewarding, developing cravings in the first weeks of smoking. People who are naturally more sensitive to nicotine, who remember more of a hit of relaxation, dizziness and nausea from their first cigarette, seem more likely to get hooked, though everyone is vulnerable to tobacco addiction.

To an addicted smoker who is tolerant of inhaling smoke, smoking satisfies a craving, may give a buzz, and can give a feeling of enhanced, calm focus. Smokers often say that cigarettes help them relax, but this is only half the story. In fact smokers are more stressed over the day than non-smokers because of their nicotine dependency, and the relaxation a cigarette gives is a temporary relief from that increased stress. After a cigarette, people who are addicted will begin the cycle of gradually worsening mood, increasing irritability and rising craving, until the next cigarette.

The rituals of smoking, including rolling and lighting cigarettes, clipping cigars or preparing a pipe, become an important part of the experience and built into the craving.

Smokeless alternatives

The experience of using smoke-free alternatives varies depending on the speed with which the nicotine is delivered. Nicotine patches deliver the drug very slowly, which does the job of reducing cravings without giving the addictive little buzz that nicotine gives when it hits the brain in a rush. Inhaling on an electronic cigarette may be comparable to smoking in delivering nicotine to the brain. Chewing tobaccos, snus and nicotine gum are probably somewhere in between.

Currently nicotine has no medical use but it does have some useful properties and it, or related but less problematic substances  could be useful in the future in preventing or treating some conditions such as Tourette’s syndrome, depression, schizophrenia or Parkinson’s disease.

It is suspected that many people with mental illnesses, especially schizophrenia, already use tobacco to control their symptoms. However, it is unlikely that any benefits of nicotine could be worth the harms of smoking. Smoking is one of the main reasons that people with schizophrenia live shorter lives on average.

With some drugs you risk harm each time you use them but with tobacco there is an enormous risk long-term, but little risk immediately apart from the chance of an unpleasant coughing fit.

Nicotine is toxic, but it is difficult to imagine how anyone could accidentally ingest enough to be poisoned. The exception is children. Babies and toddlers have been poisoned by chewing cigarettes and swallowing nicotine products.

Experimenting with taking multiple nicotine lozenges or similar things could be harmful or fatal and anyone suspected of having somehow consumed a nicotine overdose needs very prompt medical attention.

Smoking is associated with an increased risk of smoking-related diseases but if you already suffer from any heart problems, high blood-pressure, asthma or other lung problems, or come from a family where cancer or heart conditions are common, you are at even higher risk.

For reasons that are not well understood, some mental health problems, like bipolar disorder and schizophrenia are heavily associated with smoking tobacco. If you have or have ever had one of these conditions, or if family members do, it is an extra reason to avoid ever starting to smoke, as addiction may be more likely.

Alcohol addiction and tobacco addiction are tightly associated, with a high proportion of people dependent on one substance also being dependent on the other. Alcohol seems to make people enjoy smoking more and a common trajectory of addiction is people just smoking when socialising and drinking then progressing to smoking all the time. The chance of mouth cancers is much higher in people who smoke and drink heavily, compared to people who use one but not the other drug.

It is possible that brain changes caused by nicotine addiction increase the user’s sensitivity to the rewarding aspects of drugs or other addictive activities, make the user more vulnerable to addiction generally, adding more risk to the use of any other addictive substance.

In the UK particularly, cannabis is often smoked with tobacco, even when the user does not otherwise smoke cigarettes. This is likely to cause preventable cravings for and addiction to either drug , especially the tobacco.


Nicotine is one of the most addictive drugs. Whilst people vary in their vulnerability to addiction, and a small minority of smokers seem to manage to have the occasional cigarette or cigar without becoming hooked, it is generally easy to become addicted and very hard to end an addiction. If you smoke, the Fagerström test can help you find out how addicted you are.

Nicotine excites the brain’s reward circuitry, making cigarettes moreish, but as your brain re-tunes itself to having its chemistry altered over the long-term, the effect of going too long without putting nicotine in your brain becomes increasingly punishing.

Social and cultural factors also make it easy to become a smoker and hard to quit. If you have smokers in your family or social circle you are more likely to end up addicted as you have the drug and drug use around you all the time. If you are trying to quit, or trying not to get into the habit of smoking regularly, friendly offers of a cigarette and seeing/smelling people smoking will make it really hard for you. Shops displaying cigarettes at the checkout make it easy to relapse into addiction.

Smokeless alternatives

There is strong evidence that nicotine replacement with patches, lozenges, gum etc. can help some people stop smoking, and eventually quit nicotine entirely. Quitting smoking but remaining addicted to nicotine delivered through these products is much healthier than smoking, though not as healthy as quitting nicotine entirely.

Different forms of nicotine and tobacco product will differ in their addictiveness even though the drug chemical is the same in all of them. Products which deliver a nicotine hit fast, like cigarettes and e-cigarettes, are likely to be more addictive than those which deliver nicotine slowly.

Alternatives to smoking, like e-cigarettes and snus are not as well studied as cigarettes.  It is almost certain that they are less harmful than cigarettes. However, people who don’t use nicotine and wouldn’t smoke could find these appealing, leading to new nicotine addictions. The process of becoming addicted to cigarettes requires the user to desire each cigarette more than they dislike the effects or fear the results. Alternatives which are less unpleasant than inhaling irritating, hot smoke may smooth the path to addiction. The marketing of fruit-flavoured e-cigarettes can be compared to the development of alcopops, which use appealing flavours to bypass the protective disgust people (especially the young) feel when tasting ethanol.

Nicotine withdrawal can be very unpleasant, but is not physically harmful. Just a couple of hours after having a cigarette, someone dependent on nicotine will begin to feel fidgety and stressed, craving the drug, and their heart-rate will rise. Rates of relapse after quitting are extremely high.

There are no other legal products which are as harmful as cigarettes when used as they are designed to be used. Smoking causes gradual damage to your body as well as increasing the risk of various diseases. It also harms other people who breathe the smoke. Below is just a selection of the harms of smoking. Most of these harms are not known to apply to smokeless nicotine products.

Quality of Life

Smoking damages many aspects of your quality of life as well as increasing the chance of an early death. It reduces physical fitness, making you get out of breath easily, it damages your lung’s ability to self-clean, so you may cough heavily, especially the morning. It is a major cause of male sexual dysfunction (by damaging blood-flow in the penis). Yellowing and ageing of teeth, hair and skin may mean smokers feel less attractive and the lingering smell of tobacco smoke on clothes and in homes is very unattractive to most non-smokers. Successful public health campaigns have had the side-effect of making some smokers feel guilty and stigmatised. There can be unexpected consequences, for example it may be impossible to adopt children if you smoke. It is also very expensive. Being addicted to other nicotine products may have some smaller impacts.


Around 7 in every 8 cases of lung cancer and 3 in 4 cases of oral cancer are caused by tobacco, but as well as these more obvious cancers in places the smoke contacts directly, it increases the chance of many others too, such as cervical and pancreatic cancer.

Lung disease

Smoking destroys the tiny hairs which sweep mucus up out of the lungs, allowing gunk-like mucus and tar to collect. This increases the chance of infections, and causes persistent coughing. The delicate air sacs in the lungs can break down. Chronic Obstructive Pulmonary Disease (COPD) is the term used for the often fatal disease of the lungs with progressive loss of function caused by smoking. This can potentially spoil your life long before it causes death.

Cardiovascular disease

Smoking increases the risks of heart disease, raises blood pressure and damages veins and arteries. This means that the risk of heart attacks and strokes is much increased.

Risk of breaking bones

One of many little-known risks of smoking is that it interferes with the mineralisation of bone, particularly in young women who should be storing up the strength of their ‘bone bank’ for when bones lose density in later life. Smoking leaves bones (notably hips and backbones) a little weaker and so significantly more likely to fracture, especially in older age. After quitting, it seems that bone density recovers fairly well.


As well as causing erectile dysfunction in men, smoking reduces the fertility of both sexes, and smoking whilst pregnant increases the chance of miscarriage and significantly lowers birth weights. This effect on foetuses is one of the harms which also applies to nicotine-containing products that are not smoked.

To most people’s judgement, the balance of harms against benefits from smoking is totally unequal, with a high risk of disease and death for a drug that delivers only rather mild pleasures which decrease over time. This is not just the opinion of health experts; the majority of smokers themselves want to quit. The most important elements of harm reduction for nicotine are therefore;-

• Avoiding addiction to smoking tobacco in the first place,

• If addicted already, quitting as soon as possible

• If quitting is not feasible or desired, transferring to less harmful forms of nicotine product.

Historical attempts to develop ways for people to continue smoking cigarettes whilst reducing overall harm, for example by using low-tar varieties, have proved ineffective.


Quitting smoking permanently can be really hard, and many people do not succeed on their first attempt. It is possible for motivated people to quit smoking without any help, either by cutting down gradually or just deciding to never smoke again, called ‘going cold turkey’. There is some evidence that ‘going cold turkey’ is the most likely to work overall, though different methods will work best for different people.

Depending on where you live, there are a range of sources of support to help you quit, from doctors to other community services. The support of family and friends is also helpful.

Nicotine replacement therapies, like patches and nicotine gum, are proven to help some people quit. They may help get out of the habits involved in smoking, allowing you to overcome the nicotine addiction separately.

Switching to smokeless nicotine

Quitting tobacco is the way to minimise harm, but in reality, many people struggle and fail to quit, or do not want to. These people may benefit from switching to a form of long-term nicotine addiction which is less likely to cause disease and death. There is very little evidence yet to rank the forms of smokeless tobacco in order of harmfulness, but it is likely that they all offer far less risk than smoking cigarettes.

Smoking reduces stress

Nicotine does make you relax, but nicotine addiction causes stress and worsening mood the longer it has been since the last cigarette, so in fact, a smoker suffers more stress than a non-smoker.

Occasional or ‘social’ smoking is harmless

Whilst occasional smoking is far less harmful than heavy smoking, any amount of smoking increases the risks of suffering from a huge range of diseases, many of them fatal. Occasional smoking is also highly likely to end in regular smoking. Talk to people who are addicted; many smokers who thought they were in control of their habit eventually lost control.

Nicotine itself is harmless, it’s the smoking that does the damage.

This is not that far from the truth; the vast majority of the harms of cigarettes are not caused by nicotine (although you could argue that nicotine is the ultimate cause as it keeps smokers smoking). However, it is important not to disregard nicotine and think that e-cigarettes and similar alternatives to smoking are totally harmless. Nicotine has harmful effects on blood vessels and its many effects on the brain, including addiction, can negatively affect your mood and could alter your behaviour towards other addictive substances or activities.

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