What is the treatment for impetigo of the scalp?

Treatment of Impetigo of the Scalp

For impetigo of the scalp, topical mupirocin 2% ointment applied three times daily for 5-7 days is the first-line treatment for limited lesions, while oral antibiotics are recommended for extensive disease or when topical therapy is impractical. 1

Etiology and Diagnosis

• Impetigo is a highly contagious bacterial skin infection affecting the superficial layers of the epidermis, commonly caused by Staphylococcus aureus and/or Streptococcus pyogenes 2, 1
• Diagnosis is typically made clinically, with impetigo presenting as honey-colored crusts (nonbullous type) or flaccid bullae (bullous type) 3
• Cultures of vesicle fluid, pus, or erosions may be obtained to establish the causative organism, particularly in cases of treatment failure 2

Treatment Algorithm

First-Line Treatment: Topical Antibiotics

• Mupirocin 2% ointment applied to affected areas three times daily for 5-7 days is recommended for limited lesions 1, 4
• Clinical efficacy rates for mupirocin ointment in treating impetigo have been shown to be 71-93%, with pathogen eradication rates of 94-100% 4
• Retapamulin 1% ointment applied twice daily for 5 days is an effective alternative 1

Second-Line Treatment: Oral Antibiotics

• Oral antibiotics are indicated for:
  • Extensive disease involving the scalp
  • When topical therapy is impractical
  • Failure of topical treatment
  • Presence of systemic symptoms 2, 1
• Recommended oral antibiotics include:
  • First-generation cephalosporins (e.g., cephalexin)
  • Penicillinase-resistant penicillins (e.g., dicloxacillin)
  • For penicillin-allergic patients: clindamycin, doxycycline, or macrolides 2
  • Note: Penicillin V is not recommended as it has been shown to be less effective than other antibiotics 3, 5

Special Considerations

Community-Acquired MRSA (CA-MRSA)

• In areas with high prevalence of MRSA or for patients not responding to first-line therapy, consider:
  • Trimethoprim-sulfamethoxazole
  • Clindamycin
  • Doxycycline 1

Topical vs. Oral Treatment Comparison

• Topical mupirocin has been shown to be as effective as oral erythromycin in the treatment of impetigo, with clinical efficacy rates of 93% for mupirocin vs. 78.5% for erythromycin 4
• Topical antibiotics generally have fewer side effects compared to oral antibiotics, with gastrointestinal effects being the most common adverse events with oral therapy 6
• In a study comparing topical mupirocin to oral erythromycin, mupirocin was superior in eradicating S. aureus, including antibiotic-resistant strains 7

Treatment Duration and Follow-up

• Complete the full course of prescribed antibiotics even if symptoms improve quickly 1
• If no improvement is seen within 3-5 days, consider:
  • Obtaining cultures to identify the causative organism
  • Changing to an alternative antibiotic based on local resistance patterns
  • Evaluating for possible MRSA infection 2, 1

Prevention of Spread

• Advise patients on good hygiene practices to prevent spread:
  • Regular handwashing
  • Avoiding sharing personal items
  • Covering affected areas when possible 1
• Systemic therapy is preferred for patients with numerous lesions or in outbreaks affecting several people to help decrease transmission 2