Medscape - Indication-specific dosing for Bactrim, Bactrim DS, Septra, Septra DS, Cotrim, cotrimoxazole, Sulfatrim (trimethoprim, sulfamethoxazole), frequency-based adverse effects. Sulfamethoxazole and trimethoprim is a combination antibiotic used to treat ear infections, urinary tract infections, bronchitis, traveler's diarrhea, shigellosis, and Pneumocystis jiroveci pneumonia. Sulfamethoxazole and trimethoprim combination is an antibiotic. It works by eliminating the bacteria that cause many kinds of infections. This medicine will not work for colds, flu, or other virus infections. This medicine is available only with your doctor's prescription. Bactrim and Bactrim DS are antibiotics used to treat ear infections, urinary tract infections, bronchitis, traveler's diarrhea, shigellosis, and Pneumocystis jiroveci pneumonia. Bactrim DS Tablet is a combination of two medicines: Sulfamethoxazole+Trimethoprim. It is an antibiotic used to treat certain bacterial infections and works by stopping the growth of the bacteria causing the infection. BACTRIM DS prescription and dosage information for physicians and health care professionals. Pharmacology, adverse reactions, warnings, and BACTRIM DSside effects. Find patient medical information for Sulfamethoxazole/Trimethoprim (Bactrim, Septra, others) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user.