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The molecular structure of khat
  • 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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