Is Neosporin (neomycin) effective for treating impetigo?

Neosporin is NOT Recommended for Impetigo

Neosporin (neomycin-containing triple antibiotic ointment) is not effective for impetigo and should not be used—the evidence-based first-line treatments are topical mupirocin for limited disease or oral antibiotics (cephalexin or dicloxacillin) for more extensive cases. 1, 2

Why Neosporin Fails

• Neosporin lacks adequate coverage against Staphylococcus aureus, which is the primary causative organism in both bullous and non-bullous impetigo 2
• The Infectious Diseases Society of America explicitly states that penicillin-based agents without anti-staphylococcal activity are not effective for impetigo 1
• Neomycin has poor activity against the two key pathogens: S. aureus and Streptococcus pyogenes 2

Evidence-Based Treatment Algorithm

For Limited/Localized Impetigo

• Topical mupirocin 2% ointment applied three times daily for 5-7 days is the preferred first-line treatment 1, 3
• Mupirocin has excellent activity against both S. aureus (including antibiotic-resistant strains) and S. pyogenes, achieving 100% eradication rates in clinical trials 4, 5
• Topical therapy is appropriate when lesions are few in number and localized 1

For Extensive Disease or Treatment Failure

• Switch to oral antibiotics if impetigo is extensive, not responding to topical therapy after 3-5 days, or associated with systemic symptoms 1
• For presumed methicillin-susceptible S. aureus (MSSA):
  • Cephalexin 250-500 mg four times daily for adults (25-50 mg/kg/day divided into 4 doses for children) for 7 days 1, 2
  • Dicloxacillin 250 mg four times daily for adults (25-50 mg/kg/day divided into 4 doses for children) for 7 days 1, 2

When MRSA is Suspected

• Use MRSA-active agents in areas with high MRSA prevalence or if treatment fails 2
• Clindamycin 300-450 mg three times daily for adults (20-30 mg/kg/day divided into 3 doses for children) for 7 days 1, 2
• Trimethoprim-sulfamethoxazole 1-2 double-strength tablets twice daily for adults (8-12 mg/kg/day based on trimethoprim component divided into 2 doses for children) for 7 days 1, 2

Critical Clinical Considerations

• Obtain cultures from lesions if there is treatment failure, MRSA is suspected, or in cases of recurrent infections 1
• Treatment duration should be 5-7 days for topical therapy and 5-10 days for oral antibiotics 1, 2
• Keep lesions covered with clean, dry bandages and maintain good hand hygiene to prevent spread 1, 2

Common Pitfalls to Avoid

• Do not use penicillin alone—it lacks adequate anti-staphylococcal coverage 1
• Avoid tetracyclines (doxycycline) in children under 8 years due to dental staining risk 1, 2
• Be aware that erythromycin resistance rates are rising, making it a less reliable option 2, 3
• Topical disinfectants are not useful for treating impetigo 3

Special Populations

• For pregnant patients, cephalexin is considered a safe alternative 1, 2
• For patients with penicillin allergy, clindamycin is an appropriate alternative 2