Khat
Contents
- 1 Also known as
- 2 Classification
- 3 Overview
- 4 What does it look like?
- 5 Source
- 6 Prevalence
- 7 Street price
- 8 Why take it?
- 9 What are the different forms?
- 10 How long do its effects last?
- 11 Pharmacology
- 12 Mode of use
- 13 Signs of usage
- 14 Effects
- 15 Risks
- 16 Purity
- 17 Addiction
- 18 Dangerous interactions
- 19 Withdrawal
- 20 Legality
- 21 Harm reduction
- 22 Paraphernalia
- 23 History
- 24 References
Also known as
Quat, qat, qaadka, chat, miraa, murungu, Arabian or Abyssinian tea, cathinone, cathine, Catha Edulis Forsk, Catha edulis, Cathaedulis, kaht, caat, kat, kot, khot, african salad, catha, oat, qut, chaat, tchat, qaad, jaad, Kus es Salahin, tchaad, tschut, tohat, tohai, gat
Classification
Stimulant
Overview
Khat is an East African shrub (Catha Edulis) that can grow to a height of 20 metres and is often grown alongside coffee in the highlands of Kenya, Ethiopia and Yemen.
The soft stems, bark and leaves (various shades of red, purple and green) of the plant contain the active ingredients, cathinone, cathine, cathidine, norpseudoephedrine and edulin. The cathinone bio-degrades easily rendering it practically useless a couple of days after harvest. Because of this, khat is flown into the UK at least five days a week. According to a 2005 report by the Home Office, some 5 - 7 tons a day comes into the UK, but much of it is then sent on to the US.
Khat is a stimulant, which acts on neurotransmitters in the brain and brain stem in a similar fashion to amphetamine. The drug is used by chewing or 'stored' in the cheeks and orally absorbed into the blood through the vessels in the mouth. This provides a stimulant effect with a euphoric high accompanied by a sensation down the spine and through the body. It is perhaps for this reason that khat is wrongly termed a narcotic, which it is not (narcos is Greek for sleep).
In the UK, khat is usually sold in greengrocers or market stalls, Halal butchers, cheap shop fronts or domestic dwellings set up for this purpose. The latter is the case in areas where there is a significant Somali or Yemeni population (London, Sheffield, Cardiff, Birmingham, etc). An 'average' user may chew one or two bundles per session. Khat use is a heavily social activity, with teas and resting cushions and disposal bowls typically provided [1].
Khat, pronounced 'cot', is a highly addictive drug categorised as a stimulant that creates feelings of euphoria. Khat originates from the catha edulis shrub, which grows abundantly in parts of East Africa and the Arabian Peninsula. Cathine, a Schedule IV drug, and Cathinone, a Schedule I drug, are khat's two active ingredients. The khat leaves dry within 48 hours after the plant has been cut, lessening the stimulatory effect produced by cathinone by converting it into cathine, which has a much stronger effect. According to the World Health Organization, khat is classified as an abusive drug that can produce mild to moderate psychic dependence [2].
The khat plant contains stimulant drugs (active ingredients are 'cathinone'-type chemicals), which act in a similar to amphetamine. It is grown mainly in Northeastern Africa, e.g. Yemen [1]. The leafy green shrub can grow to tree size [3].
What does it look like?
Khat is a leafy green plant [4].
Khat is usually supplied as a bundle of leaves and fresh shoots wrapped in banana leaves. It is reported to have a sharp taste and an aromatic odour. Alcoholic extracts (tinctures) of khat have occasionally been reported, especially in 'herbal high' sales outlets and at music festivals [5].
Khat are usually green but other parts of the plant can be used and are various shades of red and purple as well.
In the UK, khat is usually sold in greengrocers or market stalls, Halal butchers, cheap shop fronts or domestic dwellings set up for this purpose [1].
Khat is a flowering evergreen shrub. Khat that is sold and abused is usually just the leaves, twigs, and shoots of the Khat shrub [6].
Source
The plant is grown extensively in Sub-Saharan Africa, especially Kenya, Eritrea, Ethiopia, Somalia, and The Yemen [7].
Prevalence
Khat chewing is a traditional practice in Yemen and certain East African countries. Nevertheless, khat use is sporadically reported in Europe as a substance of choice among immigrants from Somalia, Ethiopia, Kenya and Yemen. There are a few published studies of khat use by immigrant communities in European countries. However, these have mostly been conducted in the UK, and it is unclear to what extent their findings can be assumed to reflect patterns of use elsewhere in Europe. Such reports are subject to sampling bias due to the way in which interviewees are recruited. Nonetheless, the studies available do point to significant levels of use within some migrant communities. For example, a study found that in 2005, among the Somalis interviewed, 34% had used khat in the month prior to the interview although less than 4% reported using the drug on a daily basis. Studies generally report more use of the plant among males, generally in group settings. There may be a tendency to under-report khat use among women, which is a more stigmatised behaviour and more likely to occur at home or alone. Most studies have suggested that khat users are unlikely to use other psychoactive substances, which distinguishes them from most other groups of recreational drug users in Europe, where polysubstance patterns of use are increasingly the norm. Use of khat among Somali communities has also been reported in Denmark (around 1,350 users) and Sweden (2,000 - 3,000 users) [5].
According to Home Office CSEW statistics published in 2016, 0.06% of adults aged 16 to 59 had used khat in the last year; this equates to around 20,000 people in England and Wales. This is similar to the 0.05% estimated in 2014/15, but a statistically significant fall compared with 0.2% in the previous two survey years when khat use was legal. It should also be noted that a household survey such as the CSEW may underestimate the use of substances such as khat, the use of which is concentrated in individuals of a specific national origin [8].
Street price
In the United Kingdom, a bundle of khat sells for around EUR 5, but the price is higher in countries where it is controlled. Possibly due to the lability of cathinone, khat leaves seem not to be commonly sold over the Internet, whereas internet sales of khat seeds have been observed [5].
It is sold in bundles costing from £3 to £5 [1].
Prior to prohibition, £3 - £5 per bunch [7].
It sells at about £4 a bunch [8].
Why take it?
Sought after effects
- euphoric high accompanied by a sensation down the spine and through the body,
- talkative [1],
- mild euphoria,
- mild excitement,
- alertness,
- excitement,
- dilated pupils [9].
Undesired effects
- It can cause excessive sleepiness and depression [1],
- insomnia,
- loss of appetite,
- dry mouth,
- hyperactivity,
- constipation [9].
What are the different forms?
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 [10].
How long do its effects last?
Onset of effects
- chewed - minutes [11].
Duration of effects
- chewed - 30 - 120 minutes [11].
After-effects
- chewed - 1 - 10 hours [11].
Pharmacology
Both cathinone and cathine are CNS stimulants, but have a lower potency than amphetamine. Khat consumption leads to effects that are qualitatively similar to those of amphetamine, i.e. increased blood pressure, a state of euphoria and elation with feelings of increased alertness and arousal. This may be followed by depression, irritability, anorexia and difficulty in sleeping. Frequent use of high doses may evoke psychotic reactions. Gastrointestinal effects include constipation and urine retention. The role of other constituents of the khat plant is less well understood. The euphoric effects of khat start after about one hour of chewing. Peak plasma levels of cathinone are obtained 1.5 to 3.5 hours after the onset of chewing. The mean plasma level may reach 100 ng/ml after chewing 60 g fresh khat for one hour. Cathinone is barely detectable in blood after eight hours. First-pass metabolism of cathinone in the liver leads to the formation of norephedrine. Only 2% of cathinone is excreted unchanged in the urine. The elimination half-life of cathinone is 1.5 +/– 0.8 hours and that of cathine 5.2 +/– 3.4 hours. Specific associations have been proposed between khat consumption and myocardial infarction, liver failure and oral cancer, but in many cases confounding effects could not be eliminated [5].
The primary pharmacologically active agents (metabolites) in khat are cathinone and cathine (dextro-norpseudoephedrine). These are both CNS stimulants, but have a considerably lower potency than amphetamine, one of the best known CNS stimulants. The effects of khat are broadly similar to amphetamines, in that it also produces an increase in levels of epinephrine and norepinephrine (adrenaline and noradrenaline, respectively) and serotonin.
Due to the nature of the molecular structure of the active metabolites in khat and the route of administration, the release of these transmitters is slow.
It is predominantly these cathinones in khat that provide the user with the sought after euphoric and stimulating effects [1].
Central nervous system stimulant. Khat contains the chemicals cathinone and cathine which are amphetamine-like Stimulants, but Khat is much less potent [9].
Mechanism of action
The active compounds are believed to elevate levels of dopamine and nor-adrenaline. The dopaminergic activity causes significant feelings of euphoria, reward and arousal. The nor-adrenal activity causes restlessness, excitement, anxiety and increased energy [7].
Mode of use
Most often a small bunch of its leaves are 'balled up' and chewed over a number of hours [4].
Although khat can be ingested as an infusion or smoked, by far the most common route of administration is to chew the plant. Fresh vegetable material (stems, leaves and flower buds) is chewed and the juice of the masticated material is swallowed, while the residues are spat out. Typically, an individual consumes 100--200 g of khat leaves (one bundle) in a session, and its effects last for several hours. Infusions from dried leaves are also consumed. With the exception of tobacco, the concomitant use of other drugs, including alcohol, by khat users is uncommon [5].
Khat is taken orally as a tea, chewed into a paste, smoked, or sprinkled on food. The leaves, twigs, and shoots of the khat shrub are most commonly chewed and stored in the cheek. The stimulant effect of khat is most effective when the leaves are still fresh. In fact, within 48 hours of cutting the plant, khat will begin to lose the potency of cathinone [2].
The leaves of the khat plant are chewed or 'stored' in the cheeks where the drug is orally absorbed into the blood.
An 'average' user may chew one or two bundles per session. Khat use is a heavily social activity, with teas and resting cushions and disposal bowls typically provided [1].
Khat is typically chewed like tobacco, then retained in the cheek and chewed intermittently to release the active drug, which produces a stimulant-like effect. Dried Khat leaves can be made into tea or a chewable paste, and Khat can also be smoked and even sprinkled on food [6].
Signs of usage
Khat is probably one of the easiest drugs to identify during use. The presence of herbal material, specifically leaves, stalks or bunches of khat is distinctive. Some users may chew and spit, leaving green residue with leaf material. There may be green staining to teeth.
If no plant material is present, nor staining of teeth, then khat use is hard to differentiate from another stimulant. The presenting symptoms could include elevated blood pressure, elevated heart rate, perspiration, faster breathing, agitation and restlessness. However this could be caused by other stimulants, not just khat [7].
- euphoria,
- talkativeness,
- lack of appetite,
- artificially heightened mood,
- sense of well-being [12].
Effects
Khat is a stimulant and chewing it can -
- Make people more alert and talkative,
- Produce feelings of elation,
- Suppress the appetite,
- Produce a feeling of calm if it's chewed over a few hours, with some describing it as being 'blissed out',
- Lead to periods of insomnia [4].
The effect of khat on the brain and spinal cord is similar to that of amphetamines, which are simulated through synapses. Fatigue is alleviated, appetite is reduced, attention span is decreased, and levels of alertness and motor activity are increased. Users can quickly develop a psychological dependency to the drug, which increases their confidence, friendliness, and contentment. Hallucinations, grandiose delusions, and paranoia have also been noted as side-effects of using khat. The cathinone found in the drug effects the CNS, causing an excess amount of dopamine to be produced. High accumulation of dopamine in the brain can cause hallucinations, schizophrenia, and high blood pressure [2].
Immediate effects
- fast heartbeat and breathing,
- high temperature and blood pressure,
- talking more and feeling energetic,
- reduced appetite [13].
Short-term effects
- irritability,
- insomnia,
- mild euphoria,
- mild excitement,
- physical exhaustion,
- breathing difficulties,
- constipation,
- tachycardia,
- hallucinations,
- manic behaviour,
- hyperactivity,
- increased alertness,
- increased concentration,
- increased motor activity [2].
- fast breathing,
- high temperature,
- high blood pressure,
- talking more,
- reduced appetite [13], [14].
Long-term effects
Regular use of khat may eventually cause -
- anorexia,
- gastric disorders,
- depression,
- high risk for heart disease,
- high risk for cancer of the mouth,
- tachycardia (elevated heart rate),
- liver damage,
- cardiac complications [2].
- worsening of existing mental health problems,
- sleep problems,
- impotence,
- digestive problems,
- constipation,
- sore, inflamed mouth,
- mouth cancer,
- needing to use more to get the same effect,
- dependence on khat,
- financial, work and social problems [15], [14],
- mania,
- aggression,
- short psychotic episodes,
- withdrawal syndrome and cravings [12].
Overdose
- delusions,
- loss of appetite,
- difficulty with breathing,
- increased blood pressure and heart rate,
- liver damage (chemical hepatitis)
- myocardial infarctions [6].
Risks
Because khat is a plant, some people think that it is safe to use. But using any drug involves risk. Here's what it could do to you -
- you may develop insomnia and short-lived states of confusion.
- you can get high blood pressure, heart palpitations and heart problems with heavy use.
- as khat can cause periods of increased libido, care may be needed to minimise the risk of unsafe sex and unwanted pregnancies.
- khat can inflame the mouth and damage the teeth. It can also reduce appetite and cause constipation, and there is concern about a longer-term risk of development of mouth cancers.
- it can give you feelings of anxiety and aggression.
- it can make pre-existing mental health problems worse and can cause paranoid and psychotic reactions (which may be associated with irritability, anxiety and losing touch with reality).
- there is a small risk of significant liver disease, which has the potential to be life threatening [4].
Short-term
- anxiety,
- manic behaviour,
- paranoia,
- tolerance [9].
Long-term
- depression,
- irritability,
- psychological dependence,
- negative effects on liver function,
- susceptibility to ulcers,
- lowered libido [9].
Purity
Because khat comes in recognisable leaf form, it can't easily be cut with anything [4].
Khat varies in strength, and its strength also deteriorates after the plant is picked. Some users will argue that the quality of khat varies with country of origin, and the grade of the product harvested [7].
Addiction
Can you get addicted
Khat can make a user psychologically dependent (with craving and a desire to keep using in spite of potential harm). When some users stop using they can feel lethargic or mildly depressed and may have a withdrawal period with fine tremors and nightmares [4].
Dangerous interactions
Dangerous
- αMT
- Tramadol - Tramadol and stimulants both increase the risk of seizures.
- MAOIs - MAO-B inhibitors can increase the potency and duration of phenethylamines unpredictably. MAO-A inhibitors with amphetamine can lead to hypertensive crises [11].
Unsafe
- DOx - The combined stimulating effects of the two can lead to an uncomfortable body-load, while the focusing effects of amphetamine can easily lead to thought loops. Coming down from amphetamines while the DOx is still active can be quite anxiogenic.
- NBOMes - Amphetamines and NBOMes both provide considerable stimulation. When combined they can result in tachycardia, hypertension, vasoconstriction and in extreme cases heart failure. The anxiogenic and focusing effects of stimulants are also not good in combination with psychedelics as they can lead to unpleasant thought loops. NBOMes are known to cause seizures and stimulants can increase this risk.
- 2C-T-x - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences. In extreme cases, they can result in severe vasoconstriction, tachycardia, hypertension, and in extreme cases heart failure.
- 5-MeO-xxT - The anxiogenic and focusing effects of stimulants increase the chance of unpleasant thought loops. The combination is generally unnecessary because of the stimulating effects of psychedelics.
- DXM - Both substances raise heart rate, in extreme cases, panic attacks caused by these drugs have led to more serious heart issues.
- PCP - This combination can easily lead to hypermanic states [11].
Caution
- Mushrooms - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences.
- LSD - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences.
- DMT - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences.
- Mescaline - The focus and anxiety caused by stimulants is magnified by psychedelics and results in an increased risk of thought loops.
- 2C-x - The anxiogenic and focusing effects of stimulants increase the chance of unpleasant thought loops. The combination is generally uneccessary because of the stimulating effects of psychedelics. Combination of the stimulating effects may be uncomfortable.
- Cannabis - Stimulants increase anxiety levels and the risk of thought loops which can lead to negative experiences.
- Ketamine - No unexpected interactions, though likely to increase blood pressure but not an issue with sensible doses. Moving around on high doses of this combination may be ill advised due to risk of physical injury.
- MXE - Risk of tachycardia, hypertension, and manic states.
- Cocaine - This combination of stimulants will increase strain on the heart. It is not generally worth it as cocaine has a mild blocking effect on dopamine releasers like amphetamine.
- Caffeine - This combination of stimulants is not generally necessary and may increase strain on the heart, as well as potentially causing anxiety and greater physical discomfort.
- Alcohol - Drinking on stimulants is risky because the sedative effects of the alcohol are reduced, and these are what the body uses to gauge drunkenness. This typically leads to excessive drinking with greatly reduced inhibitions, high risk of liver damage and increased dehydration. They will also allow you to drink past a point where you might normally pass out, increasing the risk. If you do decide to do this then you should set a limit of how much you will drink each hour and stick to it, bearing in mind that you will feel the alcohol and the stimulant less. Extended release formulations may severely impede sleep, further worsening the hangover.
- GHB/GBL - Stimulants increase respiration rate allowing a higher dose of sedatives. If the stimulant wears off first then the opiate may overcome the patient and cause respiratory arrest.
- Opioids - Stimulants increase respiration rate allowing a higher dose of opiates. If the stimulant wears off first then the opiate may overcome the patient and cause respiratory arrest [11].
Withdrawal
Giving up khat after using it for a long time is challenging because the body has to get used to functioning without it.
It's not clear whether it's possible to become dependent on khat, but there is some evidence to suggest that if it's used heavily, withdrawal symptoms may be experienced for several days after the last time the drug was used. These symptoms may include -
- extreme tiredness,
- difficulty performing normal daily activities,
- slight trembling [16], [14],
- emotional ups and downs,
- insomnia,
- inability to focus,
- tension,
- depression,
- lethargy,
- irritability,
- anxiety [12].
Legality
On 24 June 2014 khat became a Class C drug which means it is illegal to have or to supply khat. It is also be an offence to bring khat into the country, so if you've been abroad to a country where khat is legal you cannot bring it back to the UK with you [4].
In practice those found in possession of khat for the first time are most likely to receive a warning. Khat warnings could be issued to adults from June 2014. According to the Ministry of Justice 2016 statistics there were 36,300 cannabis and khat warnings issued in the latest year, a decrease of 6,300 (15%) from the previous year [8].
What if you're caught?
If the Police catch you with khat, they'll always take some action. This could include a penalty notice, a formal caution, or arrest and possible conviction.
If you are caught with khat (called possession) you could be arrested and face up to two years in prison and/or get an unlimited fine. If you are caught dealing or supplying (and that could just mean giving some to your mates) you could get up to 14 years in jail and/or get an unlimited fine.
A conviction for a drug-related offence could have a serious impact. It could make it harder, even impossible, to visit certain countries - for example the United States - and limit the types of jobs you can apply for [4].
Did you know?
- Like drinking and driving, driving while under the influence of drugs is illegal - with some drugs you can still be unfit to drive the day after using. You can get a heavy fine, be disqualified from driving or even go to prison.
- Allowing other people to supply drugs in your house or any other premises is illegal. If the police catch people supplying illegal drugs in a club they can potentially prosecute the landlord, club owner or any person concerned in the management of the premises [4].
Harm reduction
Khat is not currently regarded as a physically addictive substance. The cathinones it contains are not known to cause any long term harm. However, as with most stimulating substances, prolonged use may lead to psychological addiction (the user feels they need to keep taking it) [1].
- Chewing of khat has been known to produce intense thirst - try to stay hydrated, but don't drink excessively as this can be just as harmful [1].
Paraphernalia
If brewed into a tea, tea making equipment [9].
History
Khat has been known in Yemen for at least 1,500 years, to where it was probably introduced from Ethiopia, although this is uncertain. Arabic medical books from at least the 11th century record its healing properties and scarcity. The renowned strength and stamina of Ethiopian warriors is often attributed to their use of khat.
The use of khat spread to the Jewish population in Yemen, and the Swedish botanist Pehr Forsskal gave the first account of its use to European audiences in 1763.
Today, the use of khat is considered to be widespread in Ethiopia, Kenya and Somalia. Communities of these nations living in London have brought much of their cultural heritage with them, and the chewing of khat in communal centres (sometimes known as 'Somali pubs') is commonplace. Until July 2013, khat was a legal substance and there was no restriction on its import. It remains to be seen how the recently announced ban will affect the trade in this substance [1].
Although khat is legal in certain parts of Europe, East Africa, and the Arabian Peninsula, it is illegal in the United States. A recreational and religious drug used commonly by natives of the source countries, khat can be found in many social environments. During the celebration of Ramadan, khat use is very popular to relieve fatigue and reduce appetite. In certain social environments, khat is used in place of alcohol. According to Arab journals from the 13th century, doctors have used khat to treat depression and lack of energy. Peasants in certain cultures who worked long hours also used this stimulant.
In countries where khat grows abundantly, the drug is found to be a large part of that country's economy. In Ethiopia, for example, khat is the 4th largest export. After being cut from a 10 to 20 ft. tall flowering evergreen shrub, khat leaves are bundled in plastic bags or banana leaves so the moisture and freshness of the active ingredients in the plant are retained as it is smuggled into the United States and any other countries [2].
References to khat use can be found in Arab journals from the 13th century. Doctors prescribed khat to treat depression and lack of energy. The stimulant effects also mean it has been commonly used by peasants who work long hours. In some Muslim countries where alcohol is banned, khat is commonly used in social situations, although khat is often condemned on religious and cultural grounds [8].
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 Khat, 2017, http://www.release.org.uk/drugs/khat
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Khat, 2013, http://www.cesar.umd.edu/cesar/drugs/khat.asp
- ↑ Khat, 2016, http://adf.org.au/drug-facts/khat/
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 Khat, 2016, http://www.talktofrank.com/drug/khat
- ↑ 5.0 5.1 5.2 5.3 5.4 Khat, 2015, http://www.emcdda.europa.eu/publications/drug-profiles/khat
- ↑ 6.0 6.1 6.2 DEA, Drugs of Abuse, 2015, Drug Enforcement Administration, https://www.dea.gov/pr/multimedia-library/publications/drug_of_abuse.pdf
- ↑ 7.0 7.1 7.2 7.3 7.4 Khat, 2017, http://www.kfx.org.uk/drug_facts/drug_facts_khat.php
- ↑ 8.0 8.1 8.2 8.3 Khat, 2016, http://www.drugwise.org.uk/khat/
- ↑ 9.0 9.1 9.2 9.3 9.4 9.5 Khat, 2014, http://www.dan247.org.uk/Drug_Khat.asp
- ↑ Khat, 2016, http://www.drugscience.org.uk/drugs/stimulants/khat/
- ↑ 11.0 11.1 11.2 11.3 11.4 11.5 Khat, 2017, http://drugs.tripsit.me/khat
- ↑ 12.0 12.1 12.2 Qat: Uses, Symptoms, Signs and Addiction Treatment, 2017, http://addictionlibrary.org/illicit/qat-uses-symptoms-signs-and-addiction-treatment.html
- ↑ 13.0 13.1 Fitzgerald, J., Khat: a literature review, 2009, https://www.researchgate.net/publication/242663060_Khat_a_literature_review
- ↑ 14.0 14.1 14.2 Khat, 2016, http://www.druginfo.adf.org.au/drug-facts/khat
- ↑ Douglas, H. and Pedder, M. and Lintzeris, N., Law enforcement and khat: An analysis of current issues, 2012, http://www.ndlerf.gov.au/sites/default/files/publication-documents/monographs/monograph40.pdf
- ↑ Cox, G. and Rampes, H., Adverse effects of khat: a review, Advances in Psychiatric Treatment, 2003, 9, 6, 456-463, http://10.1192/apt.9.6.456