Comparative Pharmacology
Head-to-head clinical analysis: SULFAMETHOPRIM DS versus SULFAMETHOXAZOLE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFAMETHOPRIM DS versus SULFAMETHOXAZOLE.
SULFAMETHOPRIM-DS vs SULFAMETHOXAZOLE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Displaces dihydropteroate synthetase from its substrate para-aminobenzoic acid (PABA), inhibiting bacterial folate synthesis. Bacteriostatic against susceptible organisms.
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.
800 mg sulfamethoxazole with 160 mg trimethoprim (DS tablet) orally every 12 hours.
None Documented
None Documented
Clinical Note
moderateSulfamethoxazole + Gatifloxacin
"Sulfamethoxazole may increase the hypoglycemic activities of Gatifloxacin."
Clinical Note
moderateSulfamethoxazole + Rosoxacin
"Sulfamethoxazole may increase the hypoglycemic activities of Rosoxacin."
Clinical Note
moderateSulfamethoxazole + Trovafloxacin
"Sulfamethoxazole may increase the hypoglycemic activities of Trovafloxacin."
Clinical Note
moderateSulfamethoxazole + Nalidixic acid
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.
9-11 hours in adults with normal renal function. Prolonged in renal impairment: up to 20-30 hours. In neonates, 6-12 hours.
Renal excretion of unchanged drug (50-70%) and metabolites (primarily N4-acetylated form, 15-30%); biliary/fecal excretion accounts for <5%.
Primarily renal; ~80-90% excreted unchanged in urine, with 15-30% as acetylated metabolite. Biliary/fecal <5%.
Category C
Category D/X
Sulfonamide Antibiotic
Sulfonamide Antibiotic
"Sulfamethoxazole may increase the hypoglycemic activities of Nalidixic acid."