Comparative Pharmacology
Head-to-head clinical analysis: SULFATRIM SS versus UROPLUS DS.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFATRIM SS versus UROPLUS DS.
SULFATRIM-SS vs UROPLUS DS
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Sulfamethoxazole inhibits bacterial dihydropteroate synthase, blocking folate synthesis. Trimethoprim inhibits bacterial dihydrofolate reductase, blocking reduction of dihydrofolate to tetrahydrofolate. Sequential blockade produces bactericidal synergy.
UROPLUS DS is a combination of sulfamethoxazole, a sulfonamide, and trimethoprim, a dihydrofolate reductase inhibitor. Sulfamethoxazole inhibits bacterial synthesis of dihydrofolic acid by competing with para-aminobenzoic acid (PABA). Trimethoprim inhibits dihydrofolate reductase, blocking the reduction of dihydrofolic acid to tetrahydrofolic acid. This sequential blockade disrupts folic acid synthesis, leading to bacterial growth inhibition.
1 double-strength tablet (160 mg trimethoprim / 800 mg sulfamethoxazole) orally every 12 hours for 10-14 days.
UROPLUS DS (methenamine mandelate 1 g + sodium acid phosphate 500 mg) oral: 1 tablet twice daily.
None Documented
None Documented
SMX: 9-12 hours (increased in renal impairment); TMP: 8-11 hours (increased in renal impairment); both prolonged in elderly.
Terminal elimination half-life is 11-13 hours in adults with normal renal function; prolonged to 16-20 hours in moderate renal impairment (CrCl 30-50 mL/min) and up to 25 hours in severe impairment (CrCl <30 mL/min).
Renal excretion of unchanged sulfamethoxazole (SMX) approximately 20%, trimethoprim (TMP) approximately 60%; biliary/fecal elimination minor (SMX <5%, TMP <10%).
Renal excretion of unchanged drug accounts for approximately 40-50% of elimination; hepatic metabolism (primarily via CYP3A4) and subsequent biliary/fecal excretion constitute the remainder with about 20-30% recovered in feces as metabolites.
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic