Sulfa Drugs

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Sulfa Drugs, common name applied to a group of chemotherapeutic agents that are effective against a number of infectious diseases. In 1935 the German chemist, Gerhard Johannes Paul Domagk discovered that an azo dye, Prontosil, cured streptococcal infections in mice. The active principle in Prontosil was found to be paraaminobenzenesulfonamide, commonly known as sulfanilamide. Clinical trials with sulfanilamide proved effective in arresting various bacterial diseases. Among the derivatives of sulfanilamide that have proved effective against such conditions as puerperal fever, scarlet fever, erysipelas, meningitis, pneumonia, and bacteremia are sulfapyridine, sulfathiazole, sulfadiazine, sulfaguanidine, sulfamerazine, and sulfasuxidine. All the sulfa drugs are somewhat toxic, producing blood abnormalities and kidney damage when indiscriminately used. Since the discovery of penicillin, which is as effective as the sulfa drugs although far less toxic, the use of sulfa drugs has somewhat declined. Because bacteria often develop resistance to a particular kind of treatment, however, sulfa drugs are used when bacterial tolerance for penicillin has developed. See Antibiotic.

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