Celastraceae

Bath salts

The term “bath salts” has been used to describe a group of drugs containing one or more cathinones, analogues of beta-ketone amphetamine. They are sold are white or brown crystalline powders in packages, as if they were proper bath salts, are often labelled “not for human consumption”. They may also be marketed as plant foods, jewellery cleaners, phone screen cleaners. They include butylone, dimethylcathinone, ethcathinone, ethylone, 3- and 4-fluoromethcathinone, mephedrone, methedrone, methylenedioxypyrovalerone (MDPV), methylone, and pyrovalerone, and are sold under brand names such as “Bloom”, “Cloud Nine”, “Ivory Wave”, “Lunar Wave”, “Scarface”, “Vanilla Sky”, and “White Lightning”.

General adverse effects and adverse reactions

Tachycardia and increased blood pressure, irritability, psychosis, and psychic dependence have been described as acute adverse effects of khat.

The long term adverse effects were well described by Louis Lewin: “Those organs functions which are incessantly subjected to the influence of the drug finally flag or are diverted into another channel of activity… The khat eater is seized with a restlessness which robs him of sleep. The excited cerebral hemispheres do not return to their normal state of repose, and in consequence the functions of the peripheral organs, especially those of the heart, suffer to such a degree that serious cardiac affectations have been ascertained in a great number of khat eaters. The disorders of the nervous system in many cases also give rise to troubles of general metabolism partly due to the chronic loss of appetite from the consumption of khat… In Yemen it was openly stated that inveterate eaters of khat were indifferent to sexual excitation and desire, and did not marry at all, or for economic reasons waited until they had saved enough money. The loss of libido has been also observed in other inhabitants of these countries.”

Cardiovascular

Khat is a sympathomimetic amine and increases blood pressure and heart rate. Limited evidence suggests that khat increases the risk of acute myocardial infarction. In Yemen 100 patients admitted to an intensive care unit with an acute myocardial infarction were compared with 100 sex- and age-matched controls recruited from an ambulatory clinic [ ]. They completed a questionnaire on personal habits, such as khat use and cigarette smoking, past medical history, and a family history of myocardial infarction. Use of khat was an independent risk factor for acute myocardial infarction, with an odds ratio of 5.0 (95% CI = 1.9, 13). The relation was dose-related: “heavy” khat users were at higher risk than “moderate” users, although the extent of use and the potency of khat used were estimated, being hard to quantify. To explain the increased risk of acute myocardial infarction, the authors suggested that it may have been related to increased blood pressure and heart rate, with a resultant increase in myocardial oxygen demand. They also suggested that khat could have acted via the mechanisms proposed to explain acute myocardial infarction after the use of amphetamines, such as catecholamine-induced platelet aggregation and coronary vasospasm.

When 80 healthy volunteers chewed fresh khat leaves for 3 hours there were significant progressive rises in systolic and diastolic blood pressures and heart rate, without return to baseline 1 hour after chewing had ceased [ ].

Of 247 chronic khat chewers 169 (62%) had hemorrhoids and 124 (45%) underwent hemorrhoidectomy; by comparison, of 200 non-khat chewers 8 (4%) had hemorrhoids and one underwent hemorrhoidectomy [ ].

Nervous system

Of 19 khat users suspected of driving under the influence of drugs, three had impaired driving and 10 had marked impairment of psychophysical functions with effects on the nervous system (slow pupil reaction to light, dry mouth, increased heart rate), trembling, restlessness/nervousness, daze/apathy/dullness, and impaired attention, walking, and standing on one leg; however, the concentrations of the khat alkaloids assayed in blood did not correlate with the symptoms of impairment [ ].

The prevalence and health effects of headache in Africa have been reviewed [ ]. In 66 khat users 25% reported headaches [ ] and in people with migraine 12% reported using khat [ ].

A leukoencephalopathy has been associated with khat [ ].

Psychiatric

Khat has amphetamine-like effects and can cause psychoses [ ], including mania [ ] and hypnagogic hallucinations [ ]. Two men developed relapsing short-lasting psychotic episodes after chewing khat leaves; the psychotic symptoms disappeared without any treatment within 1 week [ ].

In addition to the acute stimulant effects of euphoria and alertness caused by khat, there is the question of whether continued khat use alters mood, behavior, and mental health.

• A 33-year-old unemployed Somali man with a 10-year history of khat chewing, who had lived in Western Australia for 4 years, wand who was socially isolated, started to sleep badly, and had weight loss and persecutory delusions [ ]. His mental state deteriorated over 2–3 months and he thought that his relatives were poisoning him and that he was being followed by criminals. He had taken rifampicin and ethambutol for pulmonary tuberculosis for 1 year but became non-compliant for 2 months before presentation. He had reportedly chewed increasing amounts of khat daily from his backyard for last 2 years. There was no history of other drug use and his urine drug screen was negative. He responded well to olanzapine 20 mg/day and was discharged after 4 weeks, as his psychosis was gradually improving.

In Hargeisa, Somalia, trained local interviewers screened 4854 individuals for disability due to severe psychiatric problems and identified 169 cases (137 men and 32 women) [ ]. A subset of 52 positive screening cases was randomly selected for interview and were matched for age, sex, and education with controls. In all, 8.4% of men screened positive and 83% of those who screened positive had severe psychotic symptoms. Khat chewing and the use of greater amounts of khat were more common in this group. Khat users were also more likely to have had active war experience. Only 1.9% of women had positive screening. Khat use starting at an earlier age and in larger amounts (in “bundles” per day) correlated positively with psychotic symptoms.

In 800 Yemeni adults (aged 15–76 years) symptoms that might have been caused by the use of khat were elicited by face-to-face interviews; 90 items covered nine scales of the following domains: somatization, depression, anxiety, phobia, hostility, interpersonal sensitivity, obsessive-compulsive, hostility, interpersonal sensitivity, paranoia, and psychoticism [ ]. At least one life-time episode of khat use was reported in 82% of men and 43% of women. The incidence of adverse psychological symptoms was not greater in khat users, and there was a negative association between the use of khat and the incidence of phobic symptoms.

Psychological

In 25 daily khat-chewing flight attendants, 39 occasional khat-chewing flight attendants, and 24 non-khat-chewing aircrew members, memory function test scores were significantly lower in khat chewers than non-chewers and in regular chewers than occasional chewers [ ].

The impact of khat use on psychological symptoms was one of several factors considered in a study in which 180 Somali refugees were interviewed about psychological symptoms and about migration-related experiences and traumas [ ]. Suicidal thinking was more common among those who used khat (41 of 180) after migration compared with those who did not (21 of 180). However, a causal relationship cannot be deduced from these data. The authors raised the concern that khat psychosis could be increasing in Australia because of a growing number of African refugees. Furthermore, factors related to immigration, such as social displacement and unemployment, may predispose to abuse, especially as khat is easily available in Australia.

In a cross-sectional survey of Yemeni adults the self-reported frequency of khat use and psychological symptoms was assessed using face-to-face interviews with members from a random sample of urban and rural households [ ]. Of 800 adults surveyed, 82% of men and 43% of women had used khat at least once. There was no association between khat and negative adverse psychological symptoms, and khat users had less phobic anxiety (56%) than non-users (38%). The authors were surprised by these results and offered several explanations: that the form of khat used in Yemen is less potent than in other locations; that prior reports of khat-related psychosis occurred in users in unfamiliar environments; that the sampling procedure may have under-represented heavier khat users; and that their measurement tool was not sensitive enough to detect psychological symptoms.

Sensory systems

Bilateral optic atrophy occurred in two patients who were long-standing users of khat leaves and had chewed larger quantities than usual [ ].

Metabolism

Chronic khat chewing increased plasma glucose and C-peptide concentrations in people with type 2 diabetes mellitus [ ].