Table 1.

Maximum plasma and terminal half-life found in plasma of healthy human volunteers after khat chewing.

Subjects	Oral Cathinone Dose (per Kilogram of Body Weight)	Maximum Plasma Concentration	Terminal Elimination Half-Life	Ref.
Six male volunteers (25–35 years)	0.8 mg (54–71 g of fresh khat leaves)	127 ± 53 ng/mL after 2.1 ± 0.5 h	4.3 ± 1.7 h	[21]
Five volunteers (two females and three males) (21–30 years)	0.8–1 mg (60 g of fresh khat leaves)	83 ± 42 ng/mL after 1.5–3.5 h	-	[22]
Four volunteers (two male and two female) (26–57 years)	0.6 mg (26–59 g of fresh khat leaves)	58.9 ± 18.8 ng/mL after 2.31 ± 0.65 h	1.5 ± 0.8 h	[19]
Six male volunteers (28–36 years)	0.5 mg	1 h	-	[23]