sulfamethoxazole/trimethoprim is a combination antibiotic used to treat various bacterial infections. It works by inhibiting the growth of bacteria, making it effective against conditions like urinary tract infections and respiratory infections. This medication is often prescribed when other antibiotics may not be suitable. The combination consists of two components: sulfamethoxazole, which is a sulfonamide, and trimethoprim, which is a dihydrofolate reductase inhibitor. Together, they enhance each other's effectiveness, allowing for a broader range of action against bacteria. It is important to take this medication as directed by a healthcare provider to ensure its effectiveness and reduce the risk of resistance.