What is the preferred topical formulation, cream or ointment, for treating impetigo in children?

Topical Formulation for Impetigo in Children: Ointment is Preferred

For treating impetigo in children, mupirocin 2% ointment is the recommended topical formulation, applied three times daily for 5-7 days for localized disease. 1, 2

Primary Recommendation

• Mupirocin 2% ointment (not cream) is the first-line topical agent for both bullous and nonbullous impetigo in children, with demonstrated efficacy rates of 71-93%. 2
• The ointment formulation is specifically recommended in major guidelines, with application three times daily for 5-7 days. 1, 2
• Retapamulin 1% ointment applied twice daily for 5 days is an effective alternative when mupirocin is not suitable. 1, 2

Why Ointment Over Cream

The evidence consistently specifies ointment formulations rather than creams for several practical reasons:

• Ointment bases provide better occlusion and moisture retention at the infection site, enhancing drug penetration into the superficial epidermis where impetigo occurs. 3
• The ointment vehicle allows delivery of high drug concentrations directly to the site of infection with minimal systemic absorption. 3
• Clinical trials establishing efficacy for impetigo specifically used ointment formulations, not creams. 4

When Topical Therapy is Appropriate

Topical ointment therapy is suitable for:

• Limited, localized lesions affecting small areas of skin. 1
• Patients without systemic symptoms or complications. 2
• Situations where the lesions are not on the face near the eyes or mouth (though topical can still be used with caution). 1

When to Switch to Oral Antibiotics

Oral therapy becomes necessary when:

• Numerous or extensive lesions are present across multiple body sites. 1, 2
• Topical therapy fails after 48-72 hours. 2
• Systemic symptoms develop. 2
• During outbreaks affecting multiple people to decrease transmission. 1, 2
• For ecthyma (deeper ulcerative form), which always requires oral therapy. 1

For oral therapy, use dicloxacillin or cephalexin for 7 days if methicillin-susceptible S. aureus (MSSA) is suspected; use clindamycin, trimethoprim-sulfamethoxazole, or doxycycline (age >8 years) if MRSA is suspected. 1, 2

Common Pitfalls to Avoid

• Do not use penicillin alone for impetigo, as it lacks adequate coverage against S. aureus, which causes the majority of cases (85%). 2, 5
• Avoid bacitracin and neomycin as they are considerably less effective than mupirocin. 1
• Do not use topical disinfectants as they are not useful in treating impetigo. 6
• Be aware that mupirocin resistance exists, though it remains uncommon; if no improvement occurs after 48-72 hours, consider resistance or need for oral therapy. 1

Practical Application

The ointment should be applied directly to cleansed lesions with coverage extending slightly beyond the visible infection margins. 3 Lesions should be kept covered with clean, dry bandages to prevent transmission. 2 Regular hand washing and avoiding sharing personal items are essential infection control measures. 2