Bactrim Dosage and Administration Adult 1 DS tab or 2 regular tabs every 12 hours for 5 days (shigellosis, travelers' diarrhea), or 10–14 days (UTIs), or 14 days (bronchitis). For UTI, the typical Bactrim dosage for adults is either 1 or 2 tablets, depending on the strength. You will take your dose for 10-14 days. The active ingredients in Bactrim are sulfamethoxazole. Adults generally take one double-strength tablet twice daily for most infections. The duration depends on the infection type, often 3 to 14 days. For severe infections, dosing frequency and amount may increase under medical supervision. The typical dosage for Bactrim DS is 800mg/160mg (1 tablet) once daily, but the dosage may vary for different infections. Get info on dose adjustments and more. Bactrim is used to treat certain types of infections. Find out what the recommended dosages are, how to take the drug, and more. How should I use Bactrim? Take Bactrim exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Drink plenty of fluids to prevent kidney stones. Antibiotic medicines can cause diarrhea. Medscape - Indication-specific dosing for Bactrim, Bactrim DS, Septra, Septra DS, Cotrim, cotrimoxazole, Sulfatrim (trimethoprim, sulfamethoxazole), frequency-based adverse effects. Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines. Calculate trimethoprim-sulfamethoxazole dose for adults and children by weight and indication. Shows TMP and SMX components, formulation amounts for suspension, SS/DS tablets, and IV with dilution guidance. Detailed dosage guidelines and administration information for Bactrim (sulfamethoxazole and trimethoprim). Includes dose adjustments, warnings and precautions.