Comparative Pharmacology
Head-to-head clinical analysis: SULFATRIM versus SULFONAMIDES DUPLEX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFATRIM versus SULFONAMIDES DUPLEX.
SULFATRIM vs SULFONAMIDES DUPLEX
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.
Sulfonamides are competitive antagonists of para-aminobenzoic acid (PABA) and inhibit dihydropteroate synthase, blocking folate synthesis in susceptible bacteria.
160 mg trimethoprim / 800 mg sulfamethoxazole (1 DS tablet) orally every 12 hours for 10-14 days.
Oral: 500-1000 mg twice daily; maximum 2000 mg/day.
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).
Terminal half-life: 7-12 hours in patients with normal renal function; prolonged to 24-50 hours in renal impairment (CrCl <30 mL/min) due to reduced elimination.
Renal (70-80% as unchanged sulfamethoxazole and N4-acetylated metabolite; 30-40% as unchanged trimethoprim), biliary/fecal (20-30% sulfamethoxazole; 10-20% trimethoprim)
Renal: 70-100% unchanged drug via glomerular filtration and tubular secretion; fecal/biliary: <5%.
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic