How to treat impetigo that won't heal?

Treatment of Persistent Impetigo

For impetigo that won't heal, use topical mupirocin 2% ointment applied three times daily for 7-10 days as first-line treatment, or switch to oral clindamycin if there's no improvement after 3-5 days due to possible MRSA infection. 1, 2

First-Line Treatment Options

Topical Antibiotics

• Mupirocin 2% ointment: Apply three times daily for 7-10 days
  • Highly effective with 93-96% clinical efficacy rates 1, 2
  • Excellent coverage against both Staphylococcus aureus and Streptococcus pyogenes
  • Clinical trials show mupirocin is superior to placebo and equivalent or superior to oral erythromycin 2, 3
  • Apply using a gauze pad or cotton swab to affected areas 2
• Alternative topical options:
  • Retapamulin
  • Fusidic acid 1

When to Consider Oral Antibiotics

Oral antibiotics should be considered when:

• Impetigo is extensive or involves multiple sites
• Topical therapy has failed after 3-5 days
• Patient has systemic symptoms
• Compliance with topical therapy is difficult 1, 4

Management Algorithm for Non-Healing Impetigo

1. Initial Assessment:

   • Confirm diagnosis: Look for honey-colored crusts (nonbullous) or flaccid bullae (bullous)
   • Determine extent and severity of infection
   • Consider underlying conditions that may impair healing

2. First-Line Treatment:

   • Apply mupirocin 2% ointment three times daily for 7-10 days 1, 2
   • Cover with gauze dressing if desired 2
   • Advise proper hand hygiene before and after application

3. Evaluation at 48-72 hours:

   • If improving: Continue treatment for full 7-10 day course
   • If not improving: Proceed to step 4

4. For Non-Responsive Cases:

   • Obtain bacterial culture and sensitivity testing
   • Consider MRSA as possible causative organism
   • Switch to oral antibiotics 1

5. Oral Antibiotic Options:

   • First choice: Clindamycin 300mg three times daily for 7-10 days (excellent coverage against both MRSA and streptococci) 1
   • Alternatives based on suspected pathogen:
     • For MSSA: Dicloxacillin or cephalexin for 7 days
     • For confirmed streptococcal infection only: Oral penicillin for 7 days
     • AVOID: Trimethoprim-sulfamethoxazole for streptococcal infections (inadequate coverage) 1

Common Pitfalls to Avoid

1. Failure to consider resistant organisms: Community-acquired MRSA is an increasing concern in persistent impetigo 1

2. Inadequate duration of therapy: Complete the full 7-10 day course even if symptoms improve quickly 1

3. Using inappropriate antibiotics:

   • Penicillin is inferior to other antibiotics for impetigo 1, 4
   • Trimethoprim-sulfamethoxazole lacks adequate streptococcal coverage 1

4. Relying solely on topical therapy for extensive disease: Switch to oral antibiotics for widespread infection 4

5. Not addressing underlying conditions: Identify and treat conditions that may predispose to recurrent infection 1

Prevention Measures

• Keep lesions covered when possible
• Use separate towels and linens
• Practice good hand hygiene
• Avoid sharing personal items 1

Most cases of impetigo should resolve within 7-10 days with appropriate treatment. If the infection persists despite proper antibiotic therapy, consider obtaining bacterial cultures, evaluating for resistant organisms, or investigating for underlying conditions that may be impairing healing.