First-line therapy for localized impetigo in otherwise healthy individuals is which?

• A. Oral doxycycline
• B. Topical mupirocin
• C. Intravenous vancomycin
• D. Oral fluconazole

Answer: (B)

Localized impetigo is a superficial bacterial skin infection usually caused by Staphylococcus aureus or Streptococcus pyogenes. When the disease is limited to a few lesions in an otherwise healthy person, treating with a topical antibiotic is preferred because it delivers high concentrations right at the site with minimal systemic exposure. Topical mupirocin directly targets the pathogens on the skin and is effective for this scenario, making it the best first-line option. Systemic antibiotics are reserved for more extensive disease, failure of topical therapy, or systemic symptoms; intravenous vancomycin is used for severe or MRSA infections, and an antifungal like fluconazole wouldn’t treat a bacterial infection.