Comparative Pharmacology
Head-to-head clinical analysis: SULFAMETHOXAZOLE versus SULMEPRIM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFAMETHOXAZOLE versus SULMEPRIM.
SULFAMETHOXAZOLE vs SULMEPRIM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Displaces dihydropteroate synthetase from its substrate para-aminobenzoic acid (PABA), inhibiting bacterial folate synthesis. Bacteriostatic against susceptible organisms.
Sulmeprim is a combination of sulfamethoxazole, a sulfonamide, and trimethoprim, a dihydrofolate reductase inhibitor. It inhibits sequential steps in bacterial folate synthesis, leading to bactericidal activity.
800 mg sulfamethoxazole with 160 mg trimethoprim (DS tablet) orally every 12 hours.
Adults: 800 mg sulfamethoxazole/160 mg trimethoprim (one double-strength tablet) orally every 12 hours for 10-14 days. For severe infections or pneumonia, intravenous dose: 15-20 mg/kg/day (based on trimethoprim component) divided every 6-8 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
9-11 hours in adults with normal renal function. Prolonged in renal impairment: up to 20-30 hours. In neonates, 6-12 hours.
Terminal elimination half-life is 10-12 hours in patients with normal renal function, allowing twice-daily dosing. In severe renal impairment (CrCl <30 mL/min), half-life extends to >20 hours, requiring dose adjustment.
Primarily renal; ~80-90% excreted unchanged in urine, with 15-30% as acetylated metabolite. Biliary/fecal <5%.
Renal excretion of unchanged drug accounts for 70% of elimination; 20% is metabolized in the liver to inactive metabolites (glucuronide conjugates) and excreted in urine; 10% is eliminated in feces via biliary excretion.
Category D/X
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic
"Sulfamethoxazole may increase the hypoglycemic activities of Nalidixic acid."