Comparative Pharmacology
Head-to-head clinical analysis: SULTRIN versus TRIMETH SULFA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULTRIN versus TRIMETH SULFA.
SULTRIN vs TRIMETH/SULFA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Sultrin (sulfanilamide, sulfathiazole, sulfacetamide) is a triple sulfonamide combination that acts as a bacteriostatic agent. It inhibits bacterial folic acid synthesis by competing with para-aminobenzoic acid (PABA) for the active site of dihydropteroate synthase, thereby blocking the conversion of PABA to dihydrofolic acid. This disrupts nucleic acid synthesis in susceptible bacteria.
Trimethoprim inhibits bacterial dihydrofolate reductase (DHFR), blocking conversion of dihydrofolate to tetrahydrofolate; sulfamethoxazole inhibits bacterial dihydropteroate synthase, blocking incorporation of para-aminobenzoic acid into folic acid. Sequential blockade of folate synthesis produces synergistic bactericidal effect.
Intravaginal administration: one applicatorful (approximately 5 g) of Sultrin Triple Sulfa Cream (containing sulfathiazole, sulfacetamide, and sulfabenzamide) intravaginally once or twice daily for 4 to 7 days. Oral: Not applicable.
1 double-strength tablet (160 mg trimethoprim / 800 mg sulfamethoxazole) orally every 12 hours for 14 days.
None Documented
None Documented
Terminal half-life 8-12 hours; requires dose adjustment in renal impairment (CrCl <30 mL/min)
Trimethoprim: 8-11 hours; Sulfamethoxazole: 9-11 hours. Prolonged in renal impairment (up to 24-30 hours for both). Clinical context: Dosing interval is typically 12 hours in normal renal function; adjust in CrCl <15-30 mL/min.
Renal: ~70% unchanged; biliary/fecal: ~30% as metabolites
Trimethoprim: 50-60% unchanged in urine; Sulfamethoxazole: 15-30% unchanged in urine, with acetylation and glucuronidation metabolites. Approximately 80-90% of dose recovered in urine within 72 hours; remainder via feces.
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic