The pharmacokinetic properties of intramuscular quinine in Gambian children with severe falciparum malaria.

Plasma quinine concentrations were measured in 21 Gambian children with severe falciparum malaria after intramuscular administration of a 20 mg (salt) per kg loading dose of quinine dihydrochloride followed by 10 mg/kg at 12 h intervals. Quinine was well absorbed reaching mean peak concentrations of 15.6 (standard deviation [SD] 4.5) mg/litre in a median time of 3 h (range 1-6 h). A one compartment model was fitted to the plasma concentration-time profile. The mean estimated systemic clearance (Cl/F) was 0.89 (SD 0.81) ml/kg/min and the mean elimination half life was 18.8 (SD 8.0) h. Two patients, one of whom died, had low plasma quinine levels which remained below 10 mg/litre. Mean peak and trough plasma concentrations after subsequent intramuscular doses ranged between 11.1 and 15.1 mg/litre. In most cases this dose regimen provided a satisfactory profile of blood concentrations for the treatment of severe malaria in children.