Comparative Pharmacology
Head-to-head clinical analysis: SULFATRIM PEDIATRIC versus TRIMETHOPRIM SULFAMETHOXAZOLE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFATRIM PEDIATRIC versus TRIMETHOPRIM SULFAMETHOXAZOLE.
SULFATRIM PEDIATRIC vs Trimethoprim-Sulfamethoxazole
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Sulfamethoxazole inhibits dihydropteroate synthase, blocking bacterial folic acid synthesis; trimethoprim inhibits dihydrofolate reductase, blocking reduction of dihydrofolate to tetrahydrofolate. Sequential blockade leads to bactericidal activity.
Sulfamethoxazole inhibits dihydropteroate synthase, blocking para-aminobenzoic acid incorporation into dihydrofolate; trimethoprim inhibits dihydrofolate reductase, preventing tetrahydrofolate formation. Sequential blockade of folate synthesis.
Sulfatrim Pediatric suspension contains sulfamethoxazole 200 mg and trimethoprim 40 mg per 5 mL. For patients >40 kg, dose is 800 mg SMX/160 mg TMP orally every 12 hours for 10-14 days.
Oral: 160 mg TMP/800 mg SMX every 12 hours; IV: 8-10 mg/kg/day (based on TMP) in 2-4 divided doses
None Documented
None Documented
Sulfamethoxazole: 9-11 hours; Trimethoprim: 8-10 hours; prolonged in renal impairment (e.g., CrCl <30 mL/min).
Trimethoprim: 8-10 hours (normal renal function); prolonged to 24-30 hours in severe renal impairment (CrCl <10 mL/min). Sulfamethoxazole: 9-11 hours; prolonged in renal failure. The combination retains a half-life of ~10-12 hours in healthy adults, requiring dose adjustment in renal impairment.
Renal: 50-70% of total sulfamethoxazole (SMX) and 30-50% of total trimethoprim (TMP) are excreted unchanged in urine; the remainder as metabolites; biliary/fecal excretion is minimal.
Trimethoprim: 50-60% excreted unchanged in urine via glomerular filtration and tubular secretion; 10-20% as metabolites. Sulfamethoxazole: 20-30% excreted unchanged in urine; 50-70% as N4-acetylated metabolite. Both undergo minimal biliary/fecal elimination (<5% total).
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic