The toxicity of Catha edulis (khat) in mice.

A large number of people in East Africa and Southern Arabia chew khat leaves because of its pleasurable and stimulating effects. Due to its habit forming property, the khat has been classified as a "Substance of Abuse" by the World Health Organization. In view of the large number of medical problems reported in khat chewers, the present study was undertaken to investigate the chronic toxicity of khat in mice. Three groups of mice were treated with aqueous solution of khat extract in the dose of 50, 100, and 200 mg/kg. body weight daily by oral intubation route for 6 weeks. The results indicated a dose-dependent decrease in body weight, an increase in the incidence of mortality and induction of site specific body and eye lesions. The histopathological examination of the lesions revealed reactive hyperplasia and necrosis in the lymphoid tissues. The necrotic areas in the subcutaneous tissues showed the presence of numerous polymorphs.