The information below is based on NICE NG153 Impetigo: antimicrobial prescribing (February 2020).

Impetigo is a contagious, bacterial infection of the superficial layers of the skin. Impetigo affects all age groups; however, it is most common in young children.

Advise people with impetigo, and their parents or carers if appropriate, about good hygiene measures to reduce the spread of impetigo to other areas of the body and to other people.

Self-care advice:

• Wash affected areas with soap and water
• Wash hands regularly, in particular after touching a patch of impetigo
• Avoid scratching affected areas
• Avoid sharing towels, face cloths, and other personal care products and thoroughly cleanse potentially contaminated toys and play equipment

Initial treatment

Do not offer combination treatment with a topical and oral antibiotic to treat impetigo.

Localised non-bullous impetigo

Consider hydrogen peroxide 1% cream for people with localised non-bullous impetigo who are not systemically unwell or at high risk of complications, if hydrogen peroxide 1% cream is unsuitable, i.e. if ineffective or if impetigo is around eyes, offer a short course of a topical antibiotic (see below for appropriate choices).

Widespread non-bullous impetigo

Offer a short course of a topical or oral antibiotic for people with widespread non‑bullous impetigo who are not systemically unwell or at high risk of complications (see below for appropriate choices).

Bullous impetigo or impetigo in people who are systemically unwell or at high risk of complications

Offer a short course of an oral antibiotic for all people with bullous impetigo, and people with non-bullous impetigo who are systemically unwell or at high risk of complications (see below for appropriate choices).

Further treatment

For people with impetigo that is worsening or has not improved after treatment with hydrogen peroxide 1% cream, offer:

• a short course of a topical antibiotic if the impetigo remains localised or
• a short course of a topical or oral antibiotic if the impetigo has become widespread

For people with impetigo that is worsening or has not improved after completing a course of topical antibiotics:

• offer a short course of an oral antibiotic and
• consider sending a skin swab for microbiological testing

For people with impetigo that is worsening or has not improved after completing a course of oral antibiotics, consider sending a skin swab for microbiological testing

For people with impetigo that recurs frequently:

• send a skin swab for microbiological testing and
• consider taking a nasal swab and starting treatment for decolonisation

If a skin swab has been sent for microbiological testing:

• review the choice of antibiotic when results are available and
• change the antibiotic according to results if symptoms are not improving, using a narrow-spectrum antibiotic if possible

Reassessment and referral

Reassess at any time if symptoms worsen rapidly or significantly, taking account of:

• other possible diagnoses, such as herpes simplex
• any symptoms or signs suggesting a more serious illness or condition, such as cellulitis
• previous antibiotic use, which may have led to resistant bacteria.

Refer to hospital:

• people with impetigo and any symptoms or signs suggesting a more serious illness or condition (for example, cellulitis)
• people with widespread impetigo who are immunocompromised

Consider referral or seeking specialist advice for people with impetigo if they:

• have bullous impetigo, particularly in babies (aged 1 year and under)
• have impetigo that recurs frequently
• are systemically unwell
• are at high risk of complications

Consult local microbiologist if MRSA suspected or confirmed

Antimicrobials for adults aged 18 years and over

A 5‑day course is appropriate for most people with impetigo but can be increased to 7 days based on clinical judgement, depending on the severity and number of lesions.

Topical antiseptic

Hydrogen peroxide 1% cream

• Apply two or three times a day for 5 days

See section 13.11.5 Oxidisers and dyes

Topical antibiotic

Fusidic acid 2% cream/ointment

• Apply three times a day for 5 days

See section 13.10.1 Antibacterial preparations

MRSA infection in impetigo is rare, consult local microbiologist if MRSA suspected or confirmed prior to consideration of topical mupirocin

Oral antibiotic

Flucloxacillin

• 500mg four times a day for 5 days

Oral antibiotic (Penicillin allergy)

Clarithromycin

• 250mg to 500mg twice a day for 5 days
• 500mg twice a day for 5 days if severe infection

Oral antibiotic (Penicillin allergy in pregnancy)

Erythromycin

• 250mg to 500mg four times a day for 5 days
• 500mg four times a day for 5 days if severe infection

See sections 5.1.1 Penicillins and 5.1.5 Macrolides

Antimicrobials for children and young people under 18 years

A 5‑day course is appropriate for most people with impetigo but can be increased to 7 days based on clinical judgement, depending on the severity and number of lesions.

Topical antiseptic

Hydrogen peroxide 1% cream

• Apply two or three times a day for 5 days

See section 13.11.5 Oxidisers and dyes

Topical antibiotic

Fusidic acid 2% cream/ointment

• Apply three times a day for 5 days

See section 13.10.1 Antibacterial preparations

MRSA infection in impetigo is rare, consult local microbiologist if MRSA suspected or confirmed prior to consideration of topical mupirocin

Oral antibiotic

Flucloxacillin

• Children 1 month to 17 years of age (doses given four times a day for 5 days):
  • 1 month to 1 year: 62.5mg to 125mg
  • 2 to 9 years: 125mg to 250mg
  • 10 to 17 years: 250mg to 500mg

Oral antibiotic (Penicillin allergy)

Clarithromycin

• Children 1 month to 11 years of age (doses given twice daily for 5 days):
  • Body-weight under 8 kg: 7.5mg/kg
  • Body-weight 8–11 kg: 62.5mg
  • Body-weight 12–19 kg: 125mg
  • Body-weight 20–29 kg: 187.5mg
  • Body-weight 30–40 kg: 250mg
• Children 12 years to 17 years of age:
  • 250mg to 500mg twice a day for 5 days
  • 500mg twice a day for 5 days if severe infection

Oral antibiotic (Penicillin allergy in pregnancy)

Erythromycin

• Children 8 years to 17 years:
  • 250mg to 500mg four times a day for 5 days
  • 500mg four times a day for 5 days if severe infection

See sections 5.1.1 Penicillins and 5.1.5 Macrolides