Comparative Pharmacology
Head-to-head clinical analysis: TRIMETH SULFA versus TRYSUL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: TRIMETH SULFA versus TRYSUL.
TRIMETH/SULFA vs TRYSUL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Trypanocidal agent; forms a complex with DNA and inhibits nucleic acid synthesis.
1 double-strength tablet (160 mg trimethoprim / 800 mg sulfamethoxazole) orally every 12 hours for 14 days.
2 tablets (each containing sulfamethoxazole 400 mg and trimethoprim 80 mg) orally every 12 hours for 10-14 days.
None Documented
None Documented
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.
Terminal elimination half-life: 8-10 hours in adults with normal renal function; prolonged to 20-30 hours in severe renal impairment (CrCl <30 mL/min).
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.
Renal: approximately 70-80% as unchanged drug via glomerular filtration and tubular secretion; biliary/fecal: 15-20% as metabolites; small amount in feces.
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic