Mupirocin Should NOT Be Applied Around the Mouth for Impetigo
Lesions on the face, eyelid, or mouth require oral antibiotics rather than topical mupirocin, and topical therapy should be avoided in these locations. 1
Why Oral Antibiotics Are Required for Perioral Impetigo
The Clinical Infectious Diseases guidelines explicitly state that impetigo affecting the mouth area necessitates systemic treatment rather than topical therapy 1. This recommendation is based on several clinical considerations:
Anatomical concerns: The perioral area presents challenges for topical application due to inadvertent ingestion, difficulty maintaining adequate contact time, and increased moisture that reduces ointment adherence 1
Systemic absorption risk: While mupirocin shows minimal systemic absorption when applied to intact skin 2, 3, the perioral mucosa and compromised skin barrier in impetigo lesions may alter absorption characteristics
Recommended Oral Antibiotic Regimens
For Presumed Methicillin-Susceptible S. aureus (MSSA):
Dicloxacillin: 250 mg four times daily for adults; 12 mg/kg/day in 4 divided doses for children 1, 4
Cephalexin: 250-500 mg four times daily for adults; 25 mg/kg/day in 4 divided doses for children 1, 4, 5
Amoxicillin-clavulanate: 875/125 mg twice daily for adults; 25 mg/kg/day (amoxicillin component) in 2 divided doses for children 4
For Suspected or Confirmed MRSA:
Clindamycin: 300-450 mg three times daily for adults; 10-20 mg/kg/day in 3 divided doses for children 1, 4, 5
Trimethoprim-sulfamethoxazole: 1-2 double-strength tablets twice daily for adults; 8-12 mg/kg/day (trimethoprim component) in 2 divided doses for children 1, 4, 5
Treatment Duration and Monitoring
Reassessment: If no improvement occurs after 3-5 days, consider MRSA coverage, obtain cultures, and reassess for treatment failure 1, 4
Common Pitfalls to Avoid
Never use penicillin alone: It lacks adequate S. aureus coverage and is ineffective for impetigo 1, 4
Avoid tetracyclines in children under 8 years: Risk of dental staining makes doxycycline inappropriate for young children 4, 5
Consider local resistance patterns: In areas with high MRSA prevalence (>10%), empiric MRSA coverage should be initiated 5
When Mupirocin IS Appropriate
Mupirocin 2% ointment applied three times daily remains highly effective for impetigo at other body sites (trunk, extremities) with limited disease 1, 2, 6. It demonstrates 71-96% clinical efficacy rates and superior pathogen eradication compared to placebo 2, 7. However, this efficacy does not extend to perioral locations where oral therapy is mandated 1.