What is impetigo?
Impetigo is a bacterial skin infection. It is often called
school sores because it most often affects children. It is quite contagious.
What is the cause of impetigo?
What does it look like?
Impetigo presents with pustules and round, oozing patches which grow larger day by day. There may be clear blisters (bullous impetigo) or golden yellow crusts. It most often occurs on exposed areas such as the hands and face, or in skin folds particularly the armpits.
Treatment depends on the extent and severity of the infection.
- Soak moist or crusted areas
Soak a clean cloth in a mixture of half a cup of white vinegar in a litre of tepid water. Apply the compress to moist areas for about ten minutes several times a day. Gently wipe off the crusts.
- Antiseptic or antibiotic ointment
If an antiseptic (povidone iodine, hydrogen peroxide cream, chlorhexidine and others) or antibiotic ointment (fusidic acid, mupirocin or retapamulin) is prescribed, apply it two or three times a day to the affected areas and surrounding skin. Look carefully for new lesions to treat. Continue for several days after healing.
- Oral antibiotics
Oral antibiotics are recommended if the infection is extensive, proving slow to respond to topical antibiotics, or if the impetigo is recurrent. The preferred antibiotic is the penicillin antibiotic, flucloxacillin. The complete course should be taken, usually at least 7 days.
- Treat carrier sites
If impetigo is proving hard to get rid of, the following measures may be useful:
- Apply an antibiotic ointment to the nostrils three times daily for 7 days.
- Wash daily with antibacterial soap or cleanser. Soak in a bath containing a small amount of bleach.
- Take a prolonged course of oral antibiotics.
- Identify and treat the source of re-infection i.e. another infected person or carrier.
The nostrils of a household contact may be a carrier site for pathogenic bacteria, without that person having any sign of infection.
- General measures
During the infectious stage, i.e. while the impetigo is oozing or crusted:
- Cover the affected areas.
- Avoid close contact with others.
- Affected children must stay away from school until crusts have dried out.
- Use separate towels and flannels.
- Change and launder clothes and linen daily.
On DermNet NZ:
- Impetigo – pathology
- Bacterial skin infections
- Staphylococcal skin infections
- Streptococcal skin infections
- MRSA (Methicillin resistant staphylococcus aureus)
- Necrotising fasciitis
- More images of impetigo
- Bacterial infections online course for health professionals
- Impetigo – Medline Plus
- Dermatologic Manifestations of Impetigo – Medscape Reference
- Impetigo – emedicine consumer health
- Impetigo – British Association of Dermatologists
- Patient information: Impetigo (The Basics) – UpToDate (for subscribers)
- Patient information: Impetigo (Beyond the Basics) – UpToDate (for subscribers)
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