Comparative Pharmacology
Head-to-head clinical analysis: COTRIM versus SEPTRA DS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: COTRIM versus SEPTRA DS.
COTRIM vs SEPTRA DS
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
COTRIM is a combination of trimethoprim and sulfamethoxazole; sulfamethoxazole inhibits dihydropteroate synthase, and trimethoprim inhibits dihydrofolate reductase, sequentially blocking bacterial folate synthesis.
SEPTRA DS is a combination of trimethoprim and sulfamethoxazole. Trimethoprim inhibits bacterial dihydrofolate reductase, while sulfamethoxazole inhibits dihydropteroate synthase, sequentially blocking folate synthesis and ultimately DNA synthesis in susceptible bacteria.
1 double-strength tablet (160 mg trimethoprim + 800 mg sulfamethoxazole) orally every 12 hours for 5-14 days; 15-20 mg/kg/day (based on trimethoprim) IV divided every 6-8 hours for severe infections.
One DS tablet (800 mg sulfamethoxazole/160 mg trimethoprim) orally every 12 hours for 10-14 days.
None Documented
None Documented
Sulfamethoxazole: 9-11 hours (normal renal function); trimethoprim: 8-10 hours. Extended in renal impairment (SMX up to 30h, TMP up to 24h).
Trimethoprim: 8-10 hours; sulfamethoxazole: 10-12 hours (prolonged in renal impairment, e.g., creatinine clearance <30 mL/min increases half-life to >20 hours).
Renal: 50-70% unchanged sulfamethoxazole, 15-30% N4-acetylated metabolite; trimethoprim: 50-60% unchanged, 10-20% metabolites. Biliary/fecal: minimal.
Renal excretion of unchanged drugs accounts for 50-70% of trimethoprim and 20-30% of sulfamethoxazole; biliary excretion is minor (<10% total).
Category C
Category C
Antibiotic
Antibiotic