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. Key Takeaways Sulfamethoxazole is commonly used in combination with trimethoprim to treat bacterial infections. Dosage varies depending on the infection type, patient age, and kidney function. Typical adult doses range from 800 mg sulfamethoxazole combined with 160 mg trimethoprim twice daily. Children’s doses are ca. Detailed dosage guidelines and administration information for Bactrim (sulfamethoxazole and trimethoprim). Includes dose adjustments, warnings and precautions. Medscape - Indication-specific dosing for Bactrim, Bactrim DS, Septra, Septra DS, Cotrim, cotrimoxazole, Sulfatrim (trimethoprim, sulfamethoxazole), frequency-based adverse effects, comprehensive interactions, contraindications, pregnancy & lactation schedules, and cost information. Free Bactrim dosage calculator. Calculate TMP-SMX dose for adults and children by weight and indication. SS, DS tablets, suspension, and IV dosing. For treatment of bacterial infections: Adults—1 tablet (DS tablet) of 800 milligrams (mg) of sulfamethoxazole and 160 mg of trimethoprim, 2 tablets of 400 mg of sulfamethoxazole and 80 mg of trimethoprim, or 4 teaspoonfuls or 20 milliliters (mL) of oral liquid every 12 hours for 10 to 14 days. Your doctor may adjust this dose if needed. Bactrim (sulfamethoxazole and trimethoprim) is an antibiotic used to treat ear infections, urinary tract and other infections. Includes Bactrim side effects, interactions and indications. Bactrim is a prescription drug used for certain types of bacterial infections. Learn about its dosage, including its form, strengths, how it's taken, and more. Key Takeaways Bactrim is a combination antibiotic used to treat various bacterial infections. Dosage varies by form, age, and condition being treated. Typical adult doses range from 800 mg sulfamethoxazole/160 mg trimethoprim twice daily to other regimens. Children’s doses are carefully calculated by weight and condi. Bactrim is used to treat certain types of infections. Find out what the recommended dosages are, how to take the drug, and more.