Malaria prophylaxis with proguanil and sulfisoxazole in children living in a malaria endemic area.

The effects of three separate antimalarial prophylactic regimens (proguanil, sulfisoxazole, and proguanil plus sulfisoxazole) and of vitamins in a control group were compared in a study population of 380 children living in a malaria endemic area along the Thai-Burmese border. The subjects, aged 5-16 years, were matched for age, weight, and presence of splenomegaly, then randomly assigned to one of the four groups. All medications were administered daily by the investigators and malaria smears were performed on a weekly basis. Among 99 subjects taking proguanil plus sulfisoxazole for a total of 1464 man-weeks, there was only one case of falciparum and no vivax malaria. Statistically, this regimen proved superior to each of the other groups against both Plasmodium falciparum and P. vivax. The data show that proguanil alone, as a causal or suppressive prophylatic, has poor efficacy against P. falciparum. Side-effects were infrequent and generally mild, except for two subjects whose sulfisoxazole prophylaxis was discontinued because of urticarial rash.