Comparative Pharmacology
Head-to-head clinical analysis: TRIMETHOPRIM SULFAMETHOXAZOLE versus TRIPLE SULFOID.
Peer-Reviewed Evidence
Head-to-head clinical analysis: TRIMETHOPRIM SULFAMETHOXAZOLE versus TRIPLE SULFOID.
Trimethoprim-Sulfamethoxazole vs TRIPLE SULFOID
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Sulfamethoxazole inhibits dihydropteroate synthase, blocking para-aminobenzoic acid incorporation into dihydrofolate; trimethoprim inhibits dihydrofolate reductase, preventing tetrahydrofolate formation. Sequential blockade of folate synthesis.
Triple sulfoid (sulfadiazine, sulfamethazine, sulfamerazine) competes with para-aminobenzoic acid (PABA) to inhibit dihydropteroate synthase, blocking bacterial folate synthesis.
Oral: 160 mg TMP/800 mg SMX every 12 hours; IV: 8-10 mg/kg/day (based on TMP) in 2-4 divided doses
2 tablets orally every 6 hours for 10-14 days; each tablet contains sulfadiazine 270 mg, sulfamerazine 270 mg, and sulfamethazine 270 mg.
None Documented
None Documented
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.
10-12 hours in normal renal function; prolonged to 24-48 hours in severe renal impairment (CrCl <30 mL/min)
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).
Renal: ~70% as unchanged drug; hepatic metabolism: ~20%; fecal: ~10%
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic