Comparative Pharmacology
Head-to-head clinical analysis: SULFAMYLON versus TRIMETH SULFA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: SULFAMYLON versus TRIMETH SULFA.
SULFAMYLON vs TRIMETH/SULFA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Sulfamylon (mafenide acetate) is a synthetic sulfonamide that exerts bacteriostatic activity against a wide range of Gram-negative and Gram-positive organisms. It acts by inhibiting the enzyme dihydropteroate synthase, which is involved in folate synthesis, thereby blocking bacterial DNA replication. Additionally, it may be bactericidal at high concentrations via inhibition of cell wall synthesis.
Trimethoprim inhibits bacterial dihydrofolate reductase (DHFR), blocking conversion of dihydrofolate to tetrahydrofolate; sulfamethoxazole inhibits bacterial dihydropteroate synthase, blocking incorporation of para-aminobenzoic acid into folic acid. Sequential blockade of folate synthesis produces synergistic bactericidal effect.
Topical: Apply a thin layer to the wound once or twice daily. Maximum coverage area should not exceed body surface area of 20%.
1 double-strength tablet (160 mg trimethoprim / 800 mg sulfamethoxazole) orally every 12 hours for 14 days.
None Documented
None Documented
The terminal elimination half-life is approximately 7-8 hours in patients with normal renal function. In renal impairment, half-life may be prolonged, requiring dosing adjustments.
Trimethoprim: 8-11 hours; Sulfamethoxazole: 9-11 hours. Prolonged in renal impairment (up to 24-30 hours for both). Clinical context: Dosing interval is typically 12 hours in normal renal function; adjust in CrCl <15-30 mL/min.
Primarily renal excretion as unchanged drug and its metabolite; approximately 87% of a dose is recovered in urine within 24 hours as sulfacetamide and its deacetylated metabolite, with about 10% as unchanged drug. Less than 2% is excreted in feces.
Trimethoprim: 50-60% unchanged in urine; Sulfamethoxazole: 15-30% unchanged in urine, with acetylation and glucuronidation metabolites. Approximately 80-90% of dose recovered in urine within 72 hours; remainder via feces.
Category C
Category C
Sulfonamide Antibiotic
Sulfonamide Antibiotic