What is the treatment for scalp impetigo?

Treatment of Scalp Impetigo

Topical mupirocin 2% ointment applied three times daily for 5-7 days is the first-line treatment for localized scalp impetigo. 1, 2

First-Line Treatment Options

Topical Therapy

• Mupirocin 2% ointment applied three times daily for 5-7 days is the preferred topical treatment for limited scalp impetigo 3, 1, 2
• Clinical efficacy rates with mupirocin are 71-93% compared to 35% with placebo 2
• Retapamulin 1% ointment applied twice daily for 5 days is an effective alternative 4
• Topical therapy is preferred for limited disease due to fewer systemic side effects 1

Second-Line Treatment Options

Oral Antibiotics

Oral antibiotics should be used when:

• Impetigo is extensive or involves multiple sites on the scalp 1, 4
• Topical therapy is impractical 3, 1
• Treatment with topical antibiotics has failed 4
• Systemic symptoms are present 4

For Methicillin-Susceptible S. aureus (MSSA):

• Dicloxacillin: 250 mg four times daily for adults 1
• Cephalexin: 250-500 mg four times daily for adults 1, 3
• First-generation cephalosporins are generally effective as most staphylococcal isolates from impetigo are methicillin-susceptible 3

For Methicillin-Resistant S. aureus (MRSA):

• Clindamycin: 300-450 mg three times daily for adults 3, 1
• Trimethoprim-sulfamethoxazole (TMP-SMX) 3, 4
• Doxycycline (not for children under 8 years) 3

Special Considerations

Pediatric Patients

• Mupirocin has shown 78-96% clinical efficacy in pediatric populations 2
• Oral antibiotic dosing should be adjusted by weight for children 1
• Tetracyclines (doxycycline, minocycline) should not be used in children under 8 years of age 1, 3

Diagnostic Approach

• Cultures of the vesicle fluid, pus, or erosions should be obtained if there is treatment failure, MRSA is suspected, or in cases of recurrent infections 3, 1
• Unless cultures yield streptococci alone, antimicrobial therapy should be active against both S. aureus and streptococci 3

Treatment Duration and Follow-up

• Topical treatment: 5-7 days 1, 4
• Oral antibiotics: 5-10 days 1
• Re-evaluate if no improvement after 48-72 hours of therapy 1
• Keep lesions covered with clean, dry bandages and maintain good personal hygiene to prevent spread 1

Common Pitfalls and Caveats

• Penicillin alone is not effective for impetigo as it lacks adequate coverage against S. aureus 1, 5
• Topical disinfectants are inferior to antibiotics and should not be used 5, 6
• Be aware of increasing prevalence of antibiotic-resistant bacteria, including MRSA, macrolide-resistant streptococcus, and mupirocin-resistant streptococcus 5
• If impetigo is not responding to appropriate therapy, consider alternative diagnoses 1

Treatment Algorithm Summary

1. For limited scalp impetigo: Start with topical mupirocin 2% ointment three times daily for 5-7 days 1, 2
2. For extensive disease or when topical therapy is impractical: Use oral antibiotics active against both S. aureus and streptococci 3, 4
3. For suspected MRSA: Consider clindamycin, TMP-SMX, or doxycycline (age-appropriate) 3, 4
4. For treatment failure: Obtain cultures and adjust therapy based on susceptibility results 1, 3