We detected no difference in the effect on parasites and clinical illness for intrarectal quinine, but most trials were small. Pain may be less with intrarectal proprietary, buffered quinine preparations (made less acidic by adjustment of the pH to 4.5). Further larger trials in patients with severe malaria and in adults are required before the intrarectal route can be recommended.
Intrarectal pharmacokinetics of two formulations of quinine in children with falciparum malaria.
To compare the intrarectal bioavailabilities of two parenteral formulations of quinine most available in French- (Cinchona alkaloid mixture) and English (hydrochloride salt) -speaking areas of Africa.
                The pharmacokinetics of quinine was investigated in four groups of 12 children with acute Plasmodium falciparum malaria receiving 8 mg/kg quinine base every 8 h either as hydrochloride salt or Cinchona alkaloid mixture by a slow 4-h intravenous infusion or intrarectal administration. Body temperature and parasitaemia were monitored, and blood quinine concentrations were measured by means of high-performance liquid chromatography.
                At 72 h, all the children were aparasitaemic and apyretic. Quinine C(max) values were higher after intravenous infusion of the hydrochloride salt and Cinchona alkaloid mixture (6.9+/-1.9 micro g/ml and 5.2+/-1.3 micro g/ml) than after intrarectal administration (3.5+/-1.4 micro g/ml and 3.1+/-1.6 micro g/ml), but t(max) values were similar (3.6+/-1.5, 4.2+/-1.0, 4.0+/-1.9, and 4.7+/-2.0 h, respectively). Intrarectal relative bioavailabilities of hydrochloride salt solution (57%) and Cinchona alkaloid mixture (62%) were similar.
                Whatever the parenteral formulation of quinine, the blood concentration-time profiles of quinine were similar after intrarectal administration. Intrarectal administration of hydrochloride salt solution is a possible mode of quinine delivery in remote rural areas of Africa.