Low
Excellent
IV$100/d PO$1/d
Renally cleared, requires dosage adjustment with changes in renal function. Consult a pharmacist for renal dosing.
Enteric fever4 mg/kg/dose (TMP) PO q12h x 14 days
Salmonella GE, UTI4 mg/kg/dose (TMP) PO q12h x 5 days
UTI px1-2 mg/kg PO HS till 3 yrs of age
Urinary tract infections
Susceptible MRSA infections
Stenotrophomonas infections
Pneumocystis jirovecii pneumonia (treatment or prophylaxis)
Creatinine and electrolytes in patients at increased risk renal failure
Potassium
CBC
Stevens Johnson syndrome/toxic epidermal necrolysis & other rashes
Gastrointestinal upset (common)
Bone marrow suppression
Hyperkalemia
Renal failure
Hepatitis
Aseptic meningitis
Dosing is based on the trimethoprim (TMP) component
Pediatric strength tablets:100mg SMX/ 20 mg TMP
Regular strength tablets: 400mg SMX/ 80 mg TMP
Double strength tablets: 800 mg SMX/ 160 mg TMP
Suspension: (per 1 mL): 40 mg SMX/8 mg TMP
Injection: (per 1 mL): 80 mg SMX/16 mg TMP
Antimicrobial class: Sulfonamide - Antifolate
Average serum half life: TMP (prolonged in renal failure)
Newborns: ~19 hours; range: 11-27 hours
Infants 2 months to 1 year: ~4.6 hours; range: 3-6 hours
Children 1-10 years: 3.7-5.5 hours
Children and Adolescents >10 years: 8.19 hours
Adults: 6-11 hours
SMX: 9-12 hours, prolonged in renal failure (Adult data)
Route of Elimination: Both excreted in urine as metabolites and unchanged drug
