Antimalarial Activity of Sulphonamides and a Sulphone, Singly and in Combination with Pyrimethamine, against Drug Resistant and Normal Strains of Laboratory Plasmodia

Abstract

IT has been known for many years that the antimalarial action of pyrimethamine is potentiated by sulphonamides and sulphones^1,2. Although potentiating mixtures have been used clinically^3,4, they have never been used extensively in man. A disadvantage of the sulphonamides previously available is that they were excreted rapidly, and needed to be administered daily. The newer, long acting sulphonamides, however, are able to sustain a plasma concentration equal in duration to that of pyrimethamine, presenting a basis for the combined prophylactic dose to be administered at weekly intervals. Recent work⁵ has stimulated fresh interest in the action of sulphonamides and sulphonamides plus pyrimethamine combinations on malaria.