Comparative Pharmacology
Head-to-head clinical analysis: SULFAMETHOPRIM versus SULFAMETHOXAZOLE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFAMETHOPRIM versus SULFAMETHOXAZOLE.
SULFAMETHOPRIM vs SULFAMETHOXAZOLE
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.
Displaces dihydropteroate synthetase from its substrate para-aminobenzoic acid (PABA), inhibiting bacterial folate synthesis. Bacteriostatic against susceptible organisms.
Oral or intravenous: 800 mg sulfamethoxazole / 160 mg trimethoprim every 12 hours.
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: 8-12 hours in adults with normal renal function. Prolonged in renal impairment (up to 24-48 hours).
9-11 hours in adults with normal renal function. Prolonged in renal impairment: up to 20-30 hours. In neonates, 6-12 hours.
Renal: 60-80% as unchanged drug via glomerular filtration and tubular secretion; biliary: 5-10%; fecal: <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."