COMPARATIVE EFFICACY OF CHLOROQUINE PLUS CHLORPHENIRAMINE AND HALOFANTRINE IN ACUTE UNCOMPLICATED FALCIPARUM-MALARIA IN NIGERIAN CHILDREN

In the face of growing chloroquine resistance of Plasmodium falciparum , efforts to prolong the clinical usefulness of the drug have partly c oncentrated on its combination with potential resistance-reversing com pounds. However, clinical studies on such combinations have been limit ed. We have compared the efficacy of halofantrine, an arylaminoalcohol effective in chloroquine resistant malaria, and a combination of chlo roquine plus chlorpheniramine, a histamine H-1 receptor antagonist whi ch reverses chloroquine resistance of P. falciparum in vitro and in vi vo, in 100 children with acute symptomatic uncomplicated falciparum ma laria in an area of Nigeria where the rate of chloroquine resistance i s 35-45%. Both chloroquine plus chlorpheniramine and halofantrine prod uced similar parasite and fever clearance times and cure rates (96%). Both treatment regimens were relatively well tolerated. Pruritus was c ommoner in patients treated with chloroquine plus chlorpheniramine tha n in those treated with halofantrine. Intravascular haemolysis occurre d in one patient, and abdominal pain with or without diarrhoea occurre d in 4 patients, treated with halofantrine. In vitro, the chloroquine resistance of P. falciparum isolates obtained from the patients was re versed by verapamil. All patients with isolates which were chloroquine -resistant in vitro were cured by either therapy. These results indica te that chloroquine plus chlorpheniramine is as effective as halofantr ine and is without overt deleterious effect in treating acute uncompli cated chloroquine-resistant falciparum malaria in children, and may be a clinically useful alternative for this purpose in Nigeria.