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What are Sulfonamides

Sulfonamides are a group of man-made (synthetic) medicines that contain the sulfonamide chemical group. They are also called sulfa drugs (sometimes spelled as sulpha drugs or sulphonamides). Sulfanilamide was the first sulfonamide developed in 1906, although it was not used as an antimicrobial until the late 1930s. Several thousand other substances have since been developed from sulfanilamide.

Sulfonamide antimicrobials work by interfering with the synthesis of folic acid in bacteria, which is essential for nucleic acid formation and ultimately DNA and RNA. People obtain folic acid from their diet but bacteria need to synthesize it. When used alone, sulfonamides antibiotics are bacteriostatic (stop bacteria from reproducing but don't necessarily kill them); however, in combination with trimethoprim (co-trimoxazole), which acts at a different enzyme in the pathway of folic acid synthesis, sulfonamides tend to be bactericidal (kill bacteria). Many sulphonamides are rapidly excreted and very soluble in urine so they are used to treat infections of the urinary tract.

Not all sulfonamides have antibacterial activity. Thiazide diuretics, furosemide, acetazolamide, sulfonylureas and some COX-2 inhibitors are also sulfonamides.

List of Sulfonamides:

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sulfamethoxazole / trimethoprim systemic (Pro, More...)
756 reviews
sulfadiazine systemic (Pro, More...)
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sulfisoxazole systemic (More...)
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