Comparative Pharmacology
Head-to-head clinical analysis: SULFATRIM versus SULMEPRIM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFATRIM versus SULMEPRIM.
SULFATRIM vs SULMEPRIM
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.
Sulmeprim is a combination of sulfamethoxazole, a sulfonamide, and trimethoprim, a dihydrofolate reductase inhibitor. It inhibits sequential steps in bacterial folate synthesis, leading to bactericidal activity.
160 mg trimethoprim / 800 mg sulfamethoxazole (1 DS tablet) orally every 12 hours for 10-14 days.
Adults: 800 mg sulfamethoxazole/160 mg trimethoprim (one double-strength tablet) orally every 12 hours for 10-14 days. For severe infections or pneumonia, intravenous dose: 15-20 mg/kg/day (based on trimethoprim component) divided every 6-8 hours.
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 elimination half-life is 10-12 hours in patients with normal renal function, allowing twice-daily dosing. In severe renal impairment (CrCl <30 mL/min), half-life extends to >20 hours, requiring dose adjustment.
Renal (70-80% as unchanged sulfamethoxazole and N4-acetylated metabolite; 30-40% as unchanged trimethoprim), biliary/fecal (20-30% sulfamethoxazole; 10-20% trimethoprim)
Renal excretion of unchanged drug accounts for 70% of elimination; 20% is metabolized in the liver to inactive metabolites (glucuronide conjugates) and excreted in urine; 10% is eliminated in feces via biliary excretion.
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic