Comparative Pharmacology
Head-to-head clinical analysis: AZO GANTRISIN versus GANTRISIN PEDIATRIC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AZO GANTRISIN versus GANTRISIN PEDIATRIC.
AZO GANTRISIN vs GANTRISIN PEDIATRIC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Sulfamethoxazole is a competitive inhibitor of dihydropteroate synthase, blocking bacterial folic acid synthesis. Phenazopyridine is an azo dye with local analgesic effects on urinary tract mucosa.
Sulfisoxazole is a competitive inhibitor of bacterial dihydropteroate synthase, preventing the incorporation of para-aminobenzoic acid (PABA) into dihydrofolate, thereby inhibiting bacterial folic acid synthesis.
AZO GANTRISIN (phenazopyridine 100 mg / sulfisoxazole 500 mg): 2 tablets orally 4 times daily for 2 days, then 1 tablet 4 times daily for up to 5 days.
2-4 g initially, then 4-6 g/day in 3-6 divided doses orally, depending on severity. Alternatively, for sulfisoxazole (the active moiety), typical adult dose is 500 mg to 1 g orally every 6 hours. IM use: 50 mg/kg initially, then 100 mg/kg/day in divided doses every 6-8 hours. IV use: Not recommended in pediatric formulation.
None Documented
None Documented
Sulfamethoxazole: 9-12 hours (adults with normal renal function), prolonged to 20-50 hours in renal impairment; trimethoprim component: 8-11 hours. Clinical context: dosing interval adjusted based on CrCl.
Terminal elimination half-life is 6-12 hours (prolonged in renal impairment; up to 30 hours in patients with creatinine clearance <10 mL/min).
Renal: 70-100% (sulfamethoxazole and metabolites; 15-30% as unchanged drug; remainder as acetylated and glucuronide conjugates). Biliary/fecal: <3%.
Primarily renal (70-100% as unchanged drug and acetylated metabolites) via glomerular filtration and tubular secretion; <10% fecal.
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic