Sulfacetamide is a sulfonamide antibiotic that is commonly used topically to treat bacterial infections of the skin and eyes. It works by inhibiting the growth of bacteria, particularly those responsible for conditions such as acne vulgaris, seborrheic dermatitis, and ocular infections like conjunctivitis. Sulfacetamide exerts its antibacterial effects by interfering with the synthesis of folate, an essential nutrient for bacterial growth. This mechanism of action makes it effective in combating a variety of gram-positive and gram-negative bacteria, making it a versatile option for localized bacterial infections.