LACK OF EFFECT OF ORAL-CONTRACEPTIVE USE ON THE PHARMACOKINETICS OF QUININE

The pharmacokinetics of quinine after a single 600 mg oral dose of quinine sulphate were studied in seven female subjects who used oral contraceptives and in seven age-matched female controls who did not. There were no significant differences (P > 0.05) in the maximum plasma concentration (C(max)) and the time of peak concentration (t(max)) between the subjects who used oral contraceptives (C(max)) = 5.6 +/- 1.0 (s.d.) mg l(-1); t(max) = 1.4 +/- 0.7 h) and the control subjects (C(max) = 5.6 +/- 0.9 mg l(-1); t(max) = 2.1 +/- 0.9 h). The mean elimination half-life of quinine in the oral contraceptives user group (12.5 +/- 1.9 h) was similar (P > 0.05) to that in the control group (11.8 +/- 2.7 h). The oral clearance of quinine in the oral contraceptive user group was 0.133 +/- 0.055 l h-1 kg-1 (range 0.073-0.233) and was not significantly different (P > 0.05) from that observed in the control group (0.125 +/- 0.025 l h-1 kg-1, range 0.075-0.148).