Comparative Pharmacology
Head-to-head clinical analysis: LANTRISUL versus SULFAMETHOXAZOLE AND TRIMETHOPRIM DOUBLE STRENGTH.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LANTRISUL versus SULFAMETHOXAZOLE AND TRIMETHOPRIM DOUBLE STRENGTH.
LANTRISUL vs SULFAMETHOXAZOLE AND TRIMETHOPRIM DOUBLE 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 folic acid synthesis. Trimethoprim inhibits bacterial dihydrofolate reductase, blocking reduction of dihydrofolate to tetrahydrofolate. Sequential blockade produces bactericidal effect.
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.
One double-strength tablet (160 mg trimethoprim/800 mg sulfamethoxazole) orally every 12 hours.
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: 9-11 hours; trimethoprim: 8-11 hours. In severe renal impairment (CrCl <15 mL/min), half-life prolongs significantly (up to 30 hours for trimethoprim).
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.
Both sulfamethoxazole and trimethoprim are primarily excreted via the kidneys. Sulfamethoxazole: ~30% as unchanged drug, ~50% as N4-acetyl metabolite; trimethoprim: ~80% as unchanged drug. Fecal elimination is minimal (<5%).
Category C
Category D/X
Antibiotic
Antibiotic