Sulfamethoxazole is an antibiotic medication commonly used to treat various bacterial infections. Sulfamethoxazole is often combined with another antibiotic called trimethoprim and together they form a combination drug known as trimethoprim-sulfamethoxazole (TMP-SMX) or co-trimoxazole. Buy high quality Sulfamethoxazole from Molsyns Research. Molsyns Research is one of the leading manufacturer and exporter of Sulfamethoxazole