Sulfisoxazole
Sulfisoxazole is a sulfonamide antibiotic used to treat various bacterial infections. It works by inhibiting bacterial synthesis of folic acid, which is essential for bacterial growth. The medication is effective against certain gram-positive and gram-negative bacteria and is commonly prescribed for urinary tract infections and other susceptible infections.
Sulfisoxazole is a sulfonamide antibiotic that treats bacterial infections by blocking folic acid synthesis in susceptible organisms.
Key facts at a glance
- ATC
- J01EB05
- RxNorm
- 10207
- Generic
- Sulfisoxazole
- Class
- atc-j01
- Brands
- —
- Availability
- rx
- Lactation
- unknown
- Routes
- oral, ophthalmic
- Forms
- suspension, solution, tablet
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Used to treat urinary tract infections, ear infections (otitis media), bronchitis, and other infections caused by susceptible gram-positive and gram-negative bacteria. Often considered for uncomplicated UTI treatment when other options are not suitable.
Sulfisoxazole inhibits bacterial dihydropteroate synthase, an enzyme involved in folic acid synthesis. By blocking this pathway, it prevents bacteria from producing the folic acid they need to synthesize DNA and reproduce, effectively stopping bacterial growth.
Should not be used in patients with sulfonamide allergy, late pregnancy, infants under 2 months, or those with severe renal impairment. Patients should maintain adequate hydration to reduce risk of crystalluria. May cause photosensitivity reactions and blood disorders; regular monitoring may be needed during prolonged therapy.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 25, 2026. · Read our editorial policy