Mafenide Acetate 5%
Brand names: Sulfamylon
Mafenide acetate is a topical sulfonamide antimicrobial applied to burn wounds to control bacterial colonisation, valued for its ability to penetrate eschar and avascular tissue.
Adult dose
Dose adjustments
Not stated — no renal-impairment statement appears in any fetched section of this label (DOSAGE AND ADMINISTRATION, CONTRAINDICATIONS, ADVERSE REACTIONS were the only sections retrieved).
Not stated — no hepatic-impairment statement appears in any fetched section of this label.
Dose independently re-sourced from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.
Contraindications
- Hypersensitivity — CONTRAINDICATIONS verbatim: 'SULFAMYLON is contraindicated in patients who are hypersensitive to it. It is not known whether there is cross sensitivity to other sulfonamides.'
Side effects
- Dermatologic — 'The most frequently reported reaction was pain on application or a burning sensation. Rare occurrences are excoriation of new skin and bleeding of skin.'
- Allergic — 'Rash itching, facial edema, swelling, hive, blisters, erythema, and eosinophilia.'
- Respiratory — 'Tachypnea or hyperventilation, decrease in arterial pCO2.'
- Metabolic — 'Acidosis, increase in serum chloride.'
- Serious but singly reported — 'A single case of bone marrow depression and a single case of acute attack of porphyria have been reported following therapy with SULFAMYLON Cream.'
- 'Fatal hemolytic anemia with disseminated intravascular coagulation, presumably related to a glucose-6-phosphate dehydrogenase deficiency, has been reported following therapy with SULFAMYLON Cream.'
- 'Accidental ingestion of SULFAMYLON Cream has been reported to cause diarrhea.'
- General caveat from the label: 'It is frequently difficult to distinguish between an adverse reaction to SULFAMYLON Cream and the effect of a severe burn.'
Monitoring
- Acid-base balance — the label instructs interrupting treatment for acidosis: 'If acidosis occurs and becomes difficult to control, particularly in patients with pulmonary dysfunction, discontinuing therapy SULFAMYLON Cream for 24 to 48 hours while continuing fluid therapy may aid in restoring acid-base balance.'
- Respiratory pattern and arterial blood gases — the label lists 'Tachypnea or hyperventilation, decrease in arterial pCO2' as respiratory adverse reactions
- Serum chloride — listed under metabolic adverse reactions ('Acidosis, increase in serum chloride')
- Allergic manifestations — 'if allergic manifestations occur during treatment with SULFAMYLON Cream, discontinuation of treatment should be considered'
- Wound healing / readiness for grafting — treatment 'is usually continued until healing is progressing well or until the burn site is ready for grafting', and should not be withdrawn 'while there is the possibility of infection'
- No laboratory monitoring schedule is specified anywhere in the fetched label
Clinical monograph
How it works
It is a topical antibacterial agent that diffuses through devascularised burn eschar to inhibit susceptible bacteria, broadening antimicrobial cover in deep or established burn wounds.
Prescribing in practice
- Mafenide is a carbonic anhydrase inhibitor and can cause metabolic acidosis with compensatory hyperventilation, so monitor acid-base status during extensive use.
- Application can be painful and hypersensitivity reactions occur, including in patients sensitive to sulfonamides.
- Reserve for selected burn wounds under specialist burns care and follow current prescribing references, noting it is not routinely stocked in the UK.
Monitoring
Monitor acid-base balance, respiratory rate and local tolerance, particularly when treating large burn surface areas.
Counselling the patient
- Warn that application to the burn may sting or be painful.
- Advise the team to watch for rapid breathing or signs of acidosis with extensive use.
- Report any rash or worsening wound appearance to the burns team.
Evidence & guidelines
Mafenide is a long-established topical burns antimicrobial; use and its acid-base effects are described in current prescribing references and burns care literature.
Reference: British Burns Association Guidelines; ABA Burns Treatment Guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).
Related
Curated clinical cross-links plus same-class fallbacks.