How to treat impetigo (bacterial skin infection) located around the mouth?

Treatment of Impetigo Around the Mouth

For impetigo around the mouth, apply mupirocin 2% ointment three times daily for 5-7 days as first-line treatment. 1, 2, 3

First-Line Topical Therapy

• Mupirocin 2% ointment is the gold standard treatment, applied three times daily for 5-7 days, with clinical efficacy rates of 71-93% in controlled trials 2, 3
• Retapamulin 1% ointment twice daily for 5 days is an effective alternative if mupirocin is unavailable 1, 2
• Avoid bacitracin and neomycin as they are considerably less effective and should not be used 2

The perioral location does not change the treatment approach—topical therapy remains first-line for localized disease 1, 2. Mupirocin is FDA-approved specifically for impetigo caused by S. aureus and S. pyogenes, the predominant pathogens 3.

When to Escalate to Oral Antibiotics

Switch to systemic therapy if any of the following apply:

• No improvement after 48-72 hours of topical therapy 2
• Extensive disease involving multiple sites 1
• Topical therapy is impractical 1
• Systemic symptoms present (fever, malaise, lymphadenopathy) 2
• Treatment failure with topical antibiotics 1

Oral Antibiotic Selection

For presumed MSSA (Methicillin-Susceptible S. aureus):

• Dicloxacillin 250 mg four times daily for adults 1, 2
• Cephalexin 250-500 mg four times daily for adults as an alternative 1, 2

For suspected or confirmed MRSA:

• Clindamycin 300-450 mg three times daily for adults 1, 2
• Trimethoprim-sulfamethoxazole (TMP-SMX) 1-2 double-strength tablets twice daily 2
• Doxycycline (contraindicated in children under 8 years) 1, 2

Duration of oral antibiotics should be 5-10 days 1.

Critical Pitfalls to Avoid

• Never use penicillin alone—it lacks adequate coverage against S. aureus 1, 2
• Do not use rifampin as monotherapy or adjunctive therapy 2
• Tetracyclines are contraindicated in children under 8 years of age 1, 2
• Topical disinfectants are inferior to antibiotics and should not be used 4

When to Obtain Cultures

Obtain cultures from lesions if:

• Treatment failure after 48-72 hours 1, 5
• MRSA is suspected 1, 5
• Recurrent infections 1
• Severe local infection or systemic illness 5

Antimicrobial therapy should be active against both S. aureus and streptococci 1.

Infection Control Measures

• Keep lesions covered with clean, dry bandages 1
• Maintain good hand hygiene 5
• Evaluate close contacts for evidence of infection 5