Treatment of Impetigo Refractory to Mupirocin

Assessment and Management

For impetigo that is refractory to mupirocin treatment, oral antibiotics such as dicloxacillin, cephalexin, clindamycin, or amoxicillin-clavulanate should be initiated as the next step in management, as recommended by the Infectious Diseases Society of America 1, 2
Consider possible mupirocin resistance, which has been increasingly documented, especially in areas with high MRSA prevalence 2
Assess for potential MRSA infection, especially in areas with high MRSA prevalence, and consider obtaining cultures if treatment failure occurs or MRSA is suspected 2, 3
Rule out deeper infection or alternative diagnosis if clinical presentation is atypical, and re-evaluate if no improvement after 48-72 hours of oral therapy 4

Dicloxacillin: 250 mg four times daily for adults; 12 mg/kg/day in 4 divided doses for children, as recommended by the Infectious Diseases Society of America for presumed methicillin-susceptible S. aureus 1
Cephalexin: 250-500 mg four times daily for adults; 25 mg/kg/day in 4 divided doses for children, for presumed methicillin-susceptible S. aureus 1, 2
Amoxicillin-clavulanate: 875/125 mg twice daily for adults; 25 mg/kg/day of amoxicillin component in 2 divided doses for children, for presumed methicillin-susceptible S. aureus 1, 5
Clindamycin: 300-450 mg three times daily for adults; 10-20 mg/kg/day in 3 divided doses for children, for suspected or confirmed MRSA infection 1, 2
Trimethoprim-sulfamethoxazole (TMP-SMX): 1-2 double-strength tablets twice daily for adults; 8-12 mg/kg/day (based on trimethoprim component) in 2 divided doses for children, for suspected or confirmed MRSA infection 2
Doxycycline: 100 mg twice daily (not recommended for children under 8 years), for suspected or confirmed MRSA infection 2

Penicillin alone is not effective for impetigo as it lacks adequate coverage against S. aureus, according to the Infectious Diseases Society of America 3
Macrolides (e.g., erythromycin) may have increasing resistance rates and should be used with caution, as noted by the Infectious Diseases Society of America 2
For extensive impetigo, systemic therapy is preferred over topical treatment, as recommended by the Infectious Diseases Society of America 2
Consider alternative topical agents like retapamulin if available, particularly for limited lesions where topical therapy is still appropriate, according to the Infectious Diseases Society of America 3
In cases of recurrent impetigo, consider decolonization strategies for S. aureus carriers, as recommended by the Infectious Diseases Society of America 2
For pregnant patients, cephalexin is generally considered safe; avoid tetracyclines, according to the Infectious Diseases Society of America 2
For children under 8 years, avoid doxycycline and other tetracyclines, as recommended by the Infectious Diseases Society of America 1, 2
For patients with extensive disease, systemic antibiotics are preferred over topical therapy, according to the Infectious Diseases Society of America 2

The Infectious Diseases Society of America recommends topical antibiotics such as mupirocin or retapamulin as first-line therapy for limited lesions 6
The American Academy of Pediatrics and the Infectious Diseases Society of America suggest oral antibiotics such as dicloxacillin, cephalexin, clindamycin, or amoxicillin-clavulanate for extensive disease, treatment failure with topicals, or systemic symptoms 6, 7

Cefdinir can be considered as an alternative oral cephalosporin, according to the Infectious Diseases Society of America guidelines 8

The Infectious Diseases Society of America recommends starting with topical mupirocin or retapamulin for limited lesions without systemic symptoms, and switching to oral antibiotics such as dicloxacillin, cephalexin, clindamycin, or amoxicillin-clavulanate if no improvement after 3-5 days 6

For suspected or confirmed MRSA in children, the Infectious Diseases Society of America recommends clindamycin at a dose of 10-20 mg/kg/day in 3 divided doses 9
For suspected or confirmed MRSA in children, the Infectious Diseases Society of America recommends TMP-SMX at a dose of 8-12 mg/kg/day (based on trimethoprim component) in 2 divided doses 9
For children with extensive impetigo and suspected MRSA, the Infectious Diseases Society of America recommends oral clindamycin as an effective option 9
For children with MRSA, the Infectious Diseases Society of America recommends empirical therapy with clindamycin 10–13 mg/kg/dose IV every 6–8 hours if the clindamycin resistance rate is low (<10%) 9

The American Academy of Pediatrics and the Infectious Diseases Society of America advise against using tetracyclines, including doxycycline, in children under 8 years of age 9
For treatment failure with oral antibiotics, the Infectious Diseases Society of America suggests considering hospitalization with IV antibiotics such as vancomycin for MRSA 9
The Infectious Diseases Society of America recommends linezolid as an option for children with MRSA resistant to clindamycin, at a dose of 30 mg/kg/day in 3 doses for children under 12 years and 20 mg/kg/day in 2 doses for children 12 years and older 9

The Infectious Diseases Society of America recommends continuing oral antibiotics for 5-10 days 9