What is the recommended treatment and dosage of mupirocin for bacterial skin infections and MRSA decolonization?

Mupirocin Treatment Guidelines

Primary Recommendation for Bacterial Skin Infections

For bacterial skin infections, apply mupirocin 2% ointment to the affected area three times daily for 5-10 days, using a cotton swab or gauze pad, and re-evaluate if no clinical response occurs within 3-5 days. 1, 2

Dosing and Application

For Topical Skin Infections

• Apply a small amount of mupirocin 2% ointment directly to the affected area three times daily 1, 2
• Treatment duration: 5-10 days (FDA label states "up to 10 days") 3, 1
• Use a cotton swab or gauze pad for application 1
• May cover with gauze dressing if desired 1, 2
• Re-evaluate within 3-5 days if no clinical response 1, 2

For MRSA Nasal Decolonization

Apply mupirocin intranasally twice daily for 5-10 days when decolonization is indicated 3, 4

Specific decolonization protocols:

• Nasal mupirocin alone: Twice daily for 5-10 days 3
• Enhanced decolonization regimen: Intranasal mupirocin 2% twice daily for 5-7 days PLUS daily chlorhexidine body washes PLUS twice-daily chlorhexidine mouthwash 4
• For recurrent infections: Apply mupirocin in anterior nares twice daily for the first 5 days each month (reduces recurrences by ~50%) 4

When Decolonization is Appropriate

Decolonization should be considered when: 3

• A patient develops recurrent skin and soft tissue infections despite optimizing wound care and hygiene measures 3
• Ongoing transmission is occurring among household members despite hygiene measures 3
• For outbreak control in healthcare settings 4
• For cardiac surgery patients (starting at least 48 hours before surgery for 5-7 days total) 4

Clinical Indications

Appropriate Uses

• Impetigo (primary indication) 4, 5
• Secondarily infected skin lesions (infected eczema, ulcers, lacerations) 4
• Minor superficial skin infections 4, 5
• Adjunctive therapy for cutaneous abscesses after incision and drainage 4

When Mupirocin is NOT Sufficient

• Deep soft tissue infections requiring systemic antibiotics 4
• Complicated skin and soft tissue infections in hospitalized patients 4
• Cutaneous abscesses (incision and drainage is primary treatment) 4
• Infections with systemic signs (fever, extensive cellulitis, SIRS) 4
• Carbuncles and large furuncles (require incision and drainage ± systemic antibiotics) 4

Critical Precautions

Application Restrictions

• For topical use only - not for intranasal, ophthalmic, or other mucosal use (note: this refers to the topical ointment formulation, not the intranasal formulation) 1
• Do not apply concurrently with other lotions, creams, or ointments 1

Resistance Concerns

Mupirocin resistance is an emerging problem, particularly with MRSA strains 6

• A 2023 study found 22.5% of MRSA strains were mupirocin-resistant (vs. 3.0% of MSSA) 6
• High-level resistance (MIC >512 µg/mL) is associated with treatment failure 4
• Avoid prolonged or indiscriminate use to prevent resistance development 4, 7
• Unrestricted over-the-counter use and treatment of wounds/pressure sores strongly associated with resistance 8

When to Switch Strategies

Given emerging resistance patterns, consider intranasal povidone-iodine instead of mupirocin for high-risk patients (e.g., total joint replacement) colonized with MRSA 6

Common Pitfalls to Avoid

• Do not use mupirocin as monotherapy for abscesses - incision and drainage is the primary treatment 4
• Do not continue beyond 10 days without reassessment to avoid resistance 1
• Do not use for extensive infections requiring systemic therapy 4
• Do not assume efficacy in areas with high mupirocin resistance rates - consider local antibiograms 6
• Low-level resistant isolates may initially respond but commonly recolonize 8