Comparative Pharmacology
Head-to-head clinical analysis: SULFAMETHOPRIM versus SULFAMETHOPRIM DS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFAMETHOPRIM versus SULFAMETHOPRIM DS.
SULFAMETHOPRIM vs SULFAMETHOPRIM-DS
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Sulfamethoprim is a combination of sulfamethoxazole and trimethoprim. Sulfamethoxazole inhibits bacterial dihydropteroate synthase, blocking folic acid synthesis; trimethoprim inhibits bacterial dihydrofolate reductase, also blocking folic acid synthesis. This sequential blockade produces bactericidal effects.
Sulfamethoprim-DS is a combination of sulfamethoxazole, a dihydropteroate synthase inhibitor, and trimethoprim, a dihydrofolate reductase inhibitor. The sequential inhibition of folate synthesis leads to bactericidal activity.
Oral or intravenous: 800 mg sulfamethoxazole / 160 mg trimethoprim every 12 hours.
Sulfamethoprim-DS (trimethoprim 160 mg-sulfamethoxazole 800 mg) orally every 12 hours for 10-14 days for uncomplicated UTI; for Pneumocystis jirovecii pneumonia: 3-5 mg/kg/day (based on TMP) orally or IV divided every 6-8 hours for 21 days.
None Documented
None Documented
Terminal elimination half-life: 8-12 hours in adults with normal renal function. Prolonged in renal impairment (up to 24-48 hours).
Terminal elimination half-life of sulfamethoxazole is 9-11 hours (prolonged to 20-50 hours in severe renal impairment). Clinically, this supports twice-daily dosing in normal renal function; dose adjustment required for CrCl <30 mL/min.
Renal: 60-80% as unchanged drug via glomerular filtration and tubular secretion; biliary: 5-10%; fecal: <5%.
Renal excretion of unchanged drug (50-70%) and metabolites (primarily N4-acetylated form, 15-30%); biliary/fecal excretion accounts for <5%.
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic