Comparative Pharmacology
Head-to-head clinical analysis: SULFATRIM versus TRIMETHOPRIM SULFAMETHOXAZOLE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFATRIM versus TRIMETHOPRIM SULFAMETHOXAZOLE.
SULFATRIM vs Trimethoprim-Sulfamethoxazole
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Sulfatrim is a combination of sulfamethoxazole, a dihydropteroate synthase inhibitor that blocks folate synthesis, and trimethoprim, a dihydrofolate reductase inhibitor that blocks reduction of dihydrofolate to tetrahydrofolate, resulting in sequential inhibition of bacterial folate metabolism.
Sulfamethoxazole inhibits dihydropteroate synthase, blocking para-aminobenzoic acid incorporation into dihydrofolate; trimethoprim inhibits dihydrofolate reductase, preventing tetrahydrofolate formation. Sequential blockade of folate synthesis.
160 mg trimethoprim / 800 mg sulfamethoxazole (1 DS tablet) 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 (prolonged in renal impairment, e.g., up to 30 hours in severe renal failure). Trimethoprim: 8-10 hours (prolonged in hepatic impairment).
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 (70-80% as unchanged sulfamethoxazole and N4-acetylated metabolite; 30-40% as unchanged trimethoprim), biliary/fecal (20-30% sulfamethoxazole; 10-20% trimethoprim)
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