Table 3.

Pharmacological interactions between khat and clinically used drugs.

Drug Classes	Drug	Results
Anaesthetics	benoxinate (0.4%) [65]	Consumption of khat (12 h prior surgery): Reduces pain tolerance and comfort of patients during local anesthesia and surgery
	sevoflurane (2%) plus nitrous oxide (65%) [66]	Consumption of khat (4 h prior surgery): Recovery from anesthesia was delayed
Antibiotics	ampicillin (500 mg); amoxicillin (500 mg) [64] cephradine (500 mg) [63] tetracycline (500 mg) [67]	The astringent activity of tannins present in khat on GI surface can prevent/reduce absorption of oral drugs The bioavailability of both drugs was significantly reduced by khat Reductions in maximum plasma concentration, slower time for reaching peak concentration, and decrease in absorption rate

GI, gastrointestinal.