The Effect of Succinylsulfathiazole and Phthalylsulfathiazole on the Bacterial Flora of Rat Feces

Abstract

When a highly purified diet containing 0.5% to 2% succinylsulfathiazole or phthalylsulfathiazole was fed to rats over a long period of time there developed signs of nutritional deficiency which were corrected by the feeding of biotin and folic acid. The feeding of such sulfonamides also caused a decrease in the coliform count of the rat feces, but caused no significant change in the number of “total aerobes,” “total anaerobes,” or anaerobic spores in the feces. Lower levels of biotin, folic acid and pantothenic acid were excreted in the feces of rats fed diets containing the drugs than were excreted by rats fed the same diet without the drug. Neither a sulfonamide-resistant nor a sulfonamide-sensitive strain of Escherichia coli synthesized as much folic acid when grown in the presence of sulfonamides as was synthesized during growth in a medium not containing the drug.