Antimalarial Effect of Diaphenylsulfone and Three Sulfonamides among Semi-Immune Africans

Abstract

Summary Diaphenylsulfone in a single dose of 200 mg cleared asexual malarial parasitemia in semi-immune Tanzanian children aged 6 to 14 years, but doses of 50 or 100 mg were not always as effective. The period that trophozoites apparently remained absent following treatment with 200 mg, under conditions of continuous natural reinfection, was approximately 12 days. Sulforthodimethoxine, sulfadimethoxine, and sulfamethoxypyridazine in single doses of 250 mg cleared asexual parasitemia among children of similar age and immune status, whereas doses of 62.5 and 125 mg were less effective. Trophozoites remained absent for about 12 days after treatment with sulforthodimethoxine, and for a shorter period after the other two compounds.