Comparative Pharmacology
Head-to-head clinical analysis: LANTRISUL versus SEPTRA DS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LANTRISUL versus SEPTRA DS.
LANTRISUL vs SEPTRA DS
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.
SEPTRA DS is a combination of trimethoprim and sulfamethoxazole. Trimethoprim inhibits bacterial dihydrofolate reductase, while sulfamethoxazole inhibits dihydropteroate synthase, sequentially blocking folate synthesis and ultimately DNA synthesis in susceptible bacteria.
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 DS tablet (800 mg sulfamethoxazole/160 mg trimethoprim) orally every 12 hours for 10-14 days.
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.
Trimethoprim: 8-10 hours; sulfamethoxazole: 10-12 hours (prolonged in renal impairment, e.g., creatinine clearance <30 mL/min increases half-life to >20 hours).
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.
Renal excretion of unchanged drugs accounts for 50-70% of trimethoprim and 20-30% of sulfamethoxazole; biliary excretion is minor (<10% total).
Category C
Category C
Antibiotic
Antibiotic