Comparative Pharmacology
Head-to-head clinical analysis: COTRIM D S versus LANTRISUL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: COTRIM D S versus LANTRISUL.
COTRIM D.S. vs LANTRISUL
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.
Lantrisul (sulfadimethoxine) is a sulfonamide antibiotic that inhibits bacterial synthesis of dihydrofolic acid by competing with para-aminobenzoic acid (PABA) for the enzyme dihydropteroate synthase, thereby blocking folic acid synthesis and ultimately nucleic acid production in susceptible bacteria.
160 mg trimethoprim / 800 mg sulfamethoxazole (one double-strength tablet) orally every 12 hours.
Intravenous: 3 mg/kg every 8 hours for 14 days, then 5 mg/kg every 12 hours for 14 days; oral: 800 mg (10 mg/kg) twice daily after intravenous phase.
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 elimination half-life is 18 hours (range 16-20 h). This supports once-daily dosing; steady-state achieved after 3-4 days.
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%.
Approximately 70% renal excretion as unchanged drug, 15% fecal elimination via biliary secretion, 10% metabolized to inactive glucuronide conjugate eliminated renally, 5% other minor pathways.
Category C
Category C
Antibiotic
Antibiotic