Comparative Pharmacology
Head-to-head clinical analysis: ILOSONE SULFA versus SULFATRIM PEDIATRIC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ILOSONE SULFA versus SULFATRIM PEDIATRIC.
ILOSONE SULFA vs SULFATRIM PEDIATRIC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Ilosone (erythromycin) is a macrolide antibiotic that inhibits bacterial protein synthesis by binding to the 50S ribosomal subunit. Sulfa (sulfisoxazole) is a sulfonamide that inhibits dihydropteroate synthase, blocking folate synthesis. The combination provides synergistic bacteriostatic activity.
Sulfamethoxazole inhibits dihydropteroate synthase, blocking bacterial folic acid synthesis; trimethoprim inhibits dihydrofolate reductase, blocking reduction of dihydrofolate to tetrahydrofolate. Sequential blockade leads to bactericidal activity.
Each 5 mL suspension contains 250 mg erythromycin base and 600 mg sulfisoxazole; typical adult dose is 10 mL (2 tsp) every 6 hours, not to exceed 40 mL/day.
Sulfatrim Pediatric suspension contains sulfamethoxazole 200 mg and trimethoprim 40 mg per 5 mL. For patients >40 kg, dose is 800 mg SMX/160 mg TMP orally every 12 hours for 10-14 days.
None Documented
None Documented
Erythromycin: 1.5-2 hours; Sulfisoxazole: 4-7 hours; clinical context: dose adjustment in renal impairment (CrCl <50 mL/min) needed for sulfisoxazole
Sulfamethoxazole: 9-11 hours; Trimethoprim: 8-10 hours; prolonged in renal impairment (e.g., CrCl <30 mL/min).
Renal: 70-80% as unchanged drug and active metabolite (sulfisoxazole); Biliary: 10-15% as metabolites; Fecal: <5%
Renal: 50-70% of total sulfamethoxazole (SMX) and 30-50% of total trimethoprim (TMP) are excreted unchanged in urine; the remainder as metabolites; biliary/fecal excretion is minimal.
Category C
Category C
Macrolide and Sulfonamide Antibiotic
Sulfonamide Antibiotic