Comparative Pharmacology
Head-to-head clinical analysis: LANTRISUL versus SULFAMETHOXAZOLE AND TRIMETHOPRIM SINGLE STRENGTH.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LANTRISUL versus SULFAMETHOXAZOLE AND TRIMETHOPRIM SINGLE STRENGTH.
LANTRISUL vs SULFAMETHOXAZOLE AND TRIMETHOPRIM SINGLE STRENGTH
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Sulfamethoxazole inhibits bacterial dihydropteroate synthase, blocking folate synthesis. Trimethoprim inhibits bacterial dihydrofolate reductase, blocking tetrahydrofolate synthesis. Together, they provide sequential blockade of folate metabolism, leading to bactericidal activity.
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.
1 double-strength tablet (800 mg sulfamethoxazole/160 mg trimethoprim) orally every 12 hours for most infections; single-strength tablet (400 mg/80 mg) is used for prophylaxis: 1 tablet orally daily.
None Documented
None Documented
Terminal elimination half-life is 18 hours (range 16-20 h). This supports once-daily dosing; steady-state achieved after 3-4 days.
Sulfamethoxazole: 10-12 hours (prolonged in renal impairment); Trimethoprim: 8-11 hours (prolonged in hepatic impairment).
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.
Sulfamethoxazole: primarily renal (70-90% as unchanged drug and acetylated metabolite); Trimethoprim: renal (50-60% unchanged, rest as metabolites); small biliary/fecal elimination (<5% each).
Category C
Category D/X
Antibiotic
Antibiotic