Comparative Pharmacology
Head-to-head clinical analysis: COTRIM D S versus KETEK.
Peer-Reviewed Evidence
Head-to-head clinical analysis: COTRIM D S versus KETEK.
COTRIM D.S. vs KETEK
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
COTRIM D.S. is a combination of sulfamethoxazole, a competitive inhibitor of dihydropteroate synthase, and trimethoprim, a reversible inhibitor of dihydrofolate reductase. This sequential blockade of folate synthesis leads to bactericidal activity.
Telithromycin binds to the 50S subunit of bacterial ribosome, inhibiting protein synthesis by blocking peptide chain elongation.
160 mg trimethoprim / 800 mg sulfamethoxazole (one double-strength tablet) orally every 12 hours.
Telithromycin 800 mg orally once daily for 7-10 days.
None Documented
None Documented
Sulfamethoxazole: 9-12 hours (normal renal function). Trimethoprim: 8-11 hours. Both are prolonged in renal impairment (e.g., creatinine clearance <30 mL/min: >24 hours). Clinical context: dosing interval is typically 12 hours; dose adjustment required if CrCl <30 mL/min.
Terminal half-life (t½) is 9.8–10.6 hours in young healthy adults, allowing once-daily dosing. In elderly or severe hepatic impairment, t½ may be prolonged.
Sulfamethoxazole: ~20% unchanged in urine, remainder as acetylated and glucuronide metabolites. Trimethoprim: ~50-80% unchanged in urine, remainder as oxidative metabolites. Both undergo renal excretion via glomerular filtration and tubular secretion. Total renal elimination: 70-90% of dose combined. Biliary/fecal: <10%.
Primarily fecal (≈70%) via biliary excretion of unchanged drug; renal excretion accounts for ≈13% (mostly unchanged), with additional minor metabolism (<30%).
Category C
Category C
Antibiotic
Antibiotic, Ketolide