Antimicrobials
Trimethoprim-Sulfamethoxazole

Trimethoprim-Sulfamethoxazole

Low
Excellent

Dosing

General Information

  • Urinary tract infections

  • Susceptible MRSA infections

  • Stenotrophomonas infections

  • Pneumocystis jirovecii pneumonia (Treatment or prophylaxis)

Follow creatinine, BUN and serum potassium in patients at increased risk renal failure and hyperkalemia.

  • Gastrointestinal upset common
  • Bone marrow suppression
  • Reversible Hyperkalemia (with higher trimethoprim doses +/- chronic renal insufficiency or use of potassium sparing meds)
  • Renal failure
  • Hepatitis
  • Aseptic meningitis
  • Stevens Johnson syndrome/toxic epidermal necrolysis
  • Methemoglobinemia (with severe G6PD deficiency)
  • Other rashes
  • ACEi/ ARBS: Increases serum potassium level
  • Amantadine: Increases levels
  • Cyclosporine: Decreases concentration
  • Methotrexate: Marrow suppression
  • Phenytoin: Increases serum concentration
  • Rifampin: Increases levels
  • Sulfonylurea: May increase hypoglycemia
  • Warfarin: Increases INR

Antimicrobial class: Sulfonamide - Antifolate

Pregnancy category: C

Breast feeding: Compatible

Average serum half life: 10 hours

Urine penetration: Therapeutic

Lung penetration: Therapeutic

CSF penetration: Therapeutic

Biliary penetration: Moderate