Eren Oyungu1, Paul G Kioy, Nilesh B Patel. 1. Department of Medical Physiology, Moi University, P.O Box 4606, Eldoret, Kenya. erenoyungu2002@yahoo.co.uk
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE: Catha edulis (khat) is a plant whose fresh young leaves are used by an estimated five million people in eastern Africa and the Arabian Peninsula as a drug of recreation. The fresh leaves and shoots are rich in cathinone, a psychostimulant with effects similar to those of amphetamines. Psychostimulants produce a dose-related excitation of the central nervous system which can lead to seizures and convulsions. However there are no reports on studies of the effect of this herb on brain excitability and seizures. This knowledge is useful for doctors who may prescribe drugs whose side effects include lowering seizure threshold because there could be additive proconvulsant effect among khat users. AIM OF THE STUDY: to determined whether khat lowers pentylenetetrazole (PTZ) seizure threshold. METHODOLOGY: Male Sprague dawley rats were given fresh aqueous khat extract, old aqueous khat extract (3 g/kg bw), methylphenidate or saline and the timed intravenous (PTZ) seizure threshold test was used to study its effect on seizure threshold. RESULTS: Fresh khat (3 g/kg) and methylphenidate (4 mg/kg) lowered PTZ seizure threshold. CONCLUSION: Khat lowers seizure threshold.
ETHNOPHARMACOLOGICAL RELEVANCE: Catha edulis (khat) is a plant whose fresh young leaves are used by an estimated five million people in eastern Africa and the Arabian Peninsula as a drug of recreation. The fresh leaves and shoots are rich in cathinone, a psychostimulant with effects similar to those of amphetamines. Psychostimulants produce a dose-related excitation of the central nervous system which can lead to seizures and convulsions. However there are no reports on studies of the effect of this herb on brain excitability and seizures. This knowledge is useful for doctors who may prescribe drugs whose side effects include lowering seizure threshold because there could be additive proconvulsant effect among khat users. AIM OF THE STUDY: to determined whether khat lowers pentylenetetrazole (PTZ) seizure threshold. METHODOLOGY: Male Sprague dawley rats were given fresh aqueous khat extract, old aqueous khat extract (3 g/kg bw), methylphenidate or saline and the timed intravenous (PTZ) seizure threshold test was used to study its effect on seizure threshold. RESULTS: Fresh khat (3 g/kg) and methylphenidate (4 mg/kg) lowered PTZseizure threshold. CONCLUSION: Khat lowers seizure threshold.