Linezolid Dosing for Staphylococcus aureus Bullous Impetigo
For bullous impetigo caused by Staphylococcus aureus, linezolid is not a first-line agent—topical mupirocin 2% ointment applied three times daily for 5-10 days is the recommended treatment for this minor, localized skin infection. 1, 2
Why Linezolid is Not Appropriate for Bullous Impetigo
- The Infectious Diseases Society of America specifically recommends mupirocin 2% topical ointment for children with minor skin infections such as impetigo and secondarily infected skin lesions 1, 2
- Bullous impetigo represents a superficial, localized infection that does not meet criteria for complicated skin and soft tissue infection requiring systemic antibiotics 2
- Linezolid is reserved for hospitalized patients with complicated skin and soft tissue infections (cSSTI), defined as deeper soft-tissue infections, surgical/traumatic wound infections, major abscesses, cellulitis, and infected ulcers and burns 1
When Systemic Antibiotics (Including Linezolid) Would Be Indicated
If the infection progresses beyond minor impetigo or fails topical therapy, systemic antibiotics become necessary. In such cases:
For Outpatient Treatment Requiring MRSA Coverage:
- Clindamycin alone (covers both streptococci and MRSA) is preferred over linezolid for cost and practicality 1
- Trimethoprim-sulfamethoxazole plus a beta-lactam (e.g., amoxicillin) is an alternative 1
- Linezolid 600 mg orally twice daily is an option but expensive and typically reserved for more severe cases 1
For Hospitalized Patients with Complicated SSTI:
- Adults: Linezolid 600 mg IV or PO twice daily (A-I evidence) 1
- Children >12 years: Linezolid 600 mg IV or PO twice daily 1
- Children <12 years: Linezolid 10 mg/kg/dose IV or PO every 8 hours, not to exceed 600 mg/dose 1
Treatment Duration
- Treat for 5 days if clinical improvement occurs; extend only if symptoms have not improved within this timeframe 1
- For complicated SSTI in hospitalized patients, typical duration is 7-14 days based on clinical response 1
Critical Caveats
- Do not use linezolid for simple bullous impetigo—this represents significant overtreatment and unnecessary expense 1, 2
- Linezolid has equivalent efficacy to vancomycin for MRSA infections but offers no superiority 1, 3
- Adverse effects include thrombocytopenia and neuropathy, particularly with longer treatment durations (>14 days) 4
- Linezolid is a mild, reversible monoamine oxidase inhibitor—avoid coadministration with adrenergic or serotonergic agents 5