What is the treatment for impetigo?

Treatment of Impetigo

Topical mupirocin 2% ointment applied three times daily for 5-7 days is the first-line treatment for localized impetigo, while oral antibiotics should be reserved for extensive disease involving multiple sites or when topical therapy is impractical. 1

Treatment Algorithm Based on Disease Extent

Limited/Localized Disease

• Apply mupirocin 2% ointment three times daily for 5-7 days as the preferred first-line treatment 1, 2
• Retapamulin 1% ointment twice daily for 5 days is an effective alternative 3
• Topical therapy is preferred because it produces fewer systemic side effects compared to oral antibiotics 1
• Clinical efficacy rates for mupirocin reach 71-93% in clinical trials, with pathogen eradication rates of 94-100% 2

Extensive Disease or When Topical Therapy is Impractical

Use oral antibiotics when:

• Impetigo involves multiple sites or extensive areas of the body 1
• Topical application is impractical (e.g., numerous lesions, poor compliance expected) 1
• Topical treatment has failed after 48-72 hours 1
• Systemic symptoms are present 3

Oral Antibiotic Selection

For Presumed Methicillin-Susceptible S. aureus (MSSA)

• Dicloxacillin 250 mg four times daily for adults (pediatric: 12 mg/kg/day in 4 divided doses) 1
• Cephalexin 250-500 mg four times daily for adults 1
• Duration: 5-10 days 1

For Suspected or Confirmed MRSA

• Clindamycin 300-450 mg three times daily for adults 1, 3
• Trimethoprim-sulfamethoxazole (TMP-SMX) is an alternative 3
• Doxycycline is an option but avoid in children under 8 years and pregnant women 1, 3

Critical Pitfalls to Avoid

• Never use penicillin alone - it lacks adequate coverage against S. aureus, which is the primary pathogen 1, 3
• Obtain cultures from lesions if treatment fails, MRSA is suspected, or infections are recurrent 1, 3
• Re-evaluate patients if no improvement occurs after 48-72 hours of appropriate therapy 1, 3

Special Population Considerations

Pregnant Patients

• Cephalexin is generally considered safe 1
• Avoid tetracyclines (doxycycline, minocycline) 1

Pediatric Patients

• Adjust oral antibiotic dosing by weight 3
• Do not use tetracyclines in children under 8 years of age 1, 3
• Mupirocin demonstrates 78-96% clinical efficacy in pediatric populations aged 2 months to 15 years 2

Adjunctive Measures

• Keep lesions covered with clean, dry bandages 1, 3
• Maintain good personal hygiene to prevent spread 1, 3
• Consider alternative diagnoses if presentation is atypical or not responding to appropriate therapy 1