Treatment of drug-resistant malaria in man.

The progressive spread in Asia and South America of falciparum malaria resistant to 4-aminoquinolines, and the focal occurrence in all malarious regions of infections resistant to dihydrofolate dehydrogenase inhibitors such as pyrimethamine and proguanil, make it everywhere necessary to be alert to the failure of accepted curative, prophylactic, or sporontocidal chemotherapeutic agents. Resistance to 4-aminoquinolines may be met curatively with courses of treatment lasting 1-14 days, or more, the longer courses relying on quinine, often with a sulfonamide, or on tetracyclines, and the shorter courses on associations of sulfonamides or sulfones with pyrimethamine or trimethoprim. Suppressive prophylaxis of these infections is obtained by the injection at 3-month intervals of a repository mixture of acedapsone and cycloguanil, or by the weekly ingestion of sulfadoxine, sulfalene, or diformyl-dapsone associated with pyrimethamine, or the daily ingestion of dapsone with proguanil. Primaquine, although continuing to be an efficient sporontocide of P. falciparum when pyrimethamine and proguanil no longer suffice, is becoming less effective in preventing relapses of P. vivax in countries around New Guinea.