Sulphamethoxazole+Trimethoprim

DRUG INFORMATION

  ADULT
    - Pneumocystis jirovecii Pneumonia: Treatment: Adults and Children: The recommended
      dosage for treatment of patients with documented Pneumocystis jirovecii pneumonia
      is 75 to 100 mg/kg sulfamethoxazole and 15 to 20 mg/kg trimethoprim per 24 hours
      given in equally divided doses every 6 hours for 14 to 21 days.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'dosage and administration', retrieved 2026-08-29
    - Prophylaxis: Adults: The recommended dosage for prophylaxis in adults is 1
      sulfamethoxazole and trimethoprim DS (double strength) tablet daily. 13 Children:
      For children, the recommended dose is 750 mg/m 2 /day sulfamethoxazole with 150
      mg/m 2 /day trimethoprim given orally in equally divided doses twice a day, on 3
      consecutive days per week.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'dosage and administration', retrieved 2026-08-29
    - Sulfamethoxazole and trimethoprim tablets are contraindicated in pediatric
      patients less than 2 months of age. Urinary Tract Infections and Shigellosis in
      Adults and Pediatric Patients, and Acute Otitis Media in Children: Adults: The
      usual adult dosage in the treatment of urinary tract infections is 1
      sulfamethoxazole and trimethoprim DS (double strength) tablet or 2
      sulfamethoxazole and trimethoprim tablets every 12 hours for 10 to 14 days.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'dosage and administration', retrieved 2026-08-29

  CHILD
    - Sulfamethoxazole and trimethoprim is contraindicated for infants younger than 2
      months of age (see INDICATIONS AND USAGE and CONTRAINDICATIONS sections).
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'pediatric use', retrieved 2026-08-29
    - Sulfamethoxazole and trimethoprim tablets are contraindicated in pediatric
      patients less than 2 months of age. Urinary Tract Infections and Shigellosis in
      Adults and Pediatric Patients, and Acute Otitis Media in Children: Adults: The
      usual adult dosage in the treatment of urinary tract infections is 1
      sulfamethoxazole and trimethoprim DS (double strength) tablet or 2
      sulfamethoxazole and trimethoprim tablets every 12 hours for 10 to 14 days.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'dosage and administration', retrieved 2026-08-29
    - Children: The recommended dose for children with urinary tract infections or acute
      otitis media is 40 mg/kg sulfamethoxazole and 8 mg/kg trimethoprim per 24 hours,
      given in two divided doses every 12 hours for 10 days.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'dosage and administration', retrieved 2026-08-29

  RENAL IMPAIRMENT
    - No kidney-impairment dose in this label. Not a statement that none is needed.
      Source: Read and found silent: the US FDA label for sulfamethoxazole and
      trimethoprim (Sulfamethoxazole and Trimethoprim), retrieved 2026-08-29

  HEPATIC IMPAIRMENT
    - No liver-impairment dose in this label. Not a statement that none is needed.
      Source: Read and found silent: the US FDA label for sulfamethoxazole and
      trimethoprim (Sulfamethoxazole and Trimethoprim), retrieved 2026-08-29

  PREGNANCY
    - While there are no large, well-controlled studies on the use of sulfamethoxazole
      and trimethoprim in pregnant women, Brumfitt and Pursell, 11 in a retrospective
      study, reported the outcome of 186 pregnancies during which the mother received
      either placebo or sulfamethoxazole and trimethoprim.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'pregnancy', retrieved 2026-08-29
    - The incidence of congenital abnormalities was 4.5% (3 of 66) in those who received
      placebo and 3.3% (4 of 120) in those receiving sulfamethoxazole and trimethoprim.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'pregnancy', retrieved 2026-08-29
    - There were no abnormalities in the 10 children whose mothers received the drug
      during the first trimester.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'pregnancy', retrieved 2026-08-29

  BREASTFEEDING   [ CAUTION ]
    The label allows it only when the benefit is judged to outweigh the risk. Read the
      quote below.
    - Levels of sulfamethoxazole and trimethoprim in breast milk are approximately 2 to
      5% of the recommended daily dose for infants over 2 months of age.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'nursing mothers', retrieved 2026-08-29
    - Caution should be exercised when sulfamethoxazole and trimethoprim is administered
      to a nursing woman, especially when breastfeeding, jaundiced, ill, stressed, or
      premature infants because of the potential risk of bilirubin displacement and
      kernicterus.
      Source: US FDA label for sulfamethoxazole and trimethoprim (Sulfamethoxazole and
      Trimethoprim), section 'nursing mothers', retrieved 2026-08-29