Multiple dose pharmacokinetics of artemether in Chinese patients with uncomplicated falciparum malaria

Multiple dose pharmacokinetics of artemether and dihydroartemisinin were investigated in chinese patients treated for malaria. They received over 2 days either 4 x 80 mg artemether orally (n = 48) or 4 x 80-480 mg co-artemether (n = 40), a combination of artemether and lumefantrine (benflumetol). Lag time = 0.48 h (mean), C-max after first dose = 157 ng/ml, t(max) = 1.73 h and elimination half-life = 1.16 h. The lag and absorption times were 0.5 h longer for co-artemether compared with artemether. Dihydroartemisinin paralleled artemether pharmacokinetics. Artemether C-max after the last dose was one-third of the C-max after the first dose while, inversely, dihydroartemisinin C-max increased over time. We suggest that auto-induction of gut mucosa enzymes and/or liver enzymes causes a time-dependent increase in first-pass metabolisation of artemether. (C) 1999 Elsevier Science B.V. and International Society of Chemotherapy. All rights reserved.