Effect of oral contraceptive steroids on the clinical course of malaria infection and on the pharmacokinetics of mefloquine in Thai women

Abstract

The pharmacokinetics of a single oral dose of mefloquine (750 mg) were followed in six healthy Thai women volunteers who regularly used oral contraceptive steroids (OCS) and in 12 Thai women patients with falciparum malaria, six of whom were also using OCS. Those taking the contraceptives continued to do so throughout the duration of the study (42 days). Both groups of patients responded to mefloquine with parasite and fever clearance times that were not significantly different, which suggests that the OCS had no deleterious effect on the course of the disease. Also, the pharmacokinetic parameters of mefloquine were not significantly different for the two patient groups. However, both the half-life and mean residence time of mefloquine were significantly longer in the healthy volunteers than in the patients, indicating that, although OCS had no effect on the pharmacokinetics of mefloquine, falciparum malaria did cause dispositional changes.