Patients with cellulitis or erysipelas without systemic features who are at low risk of MRSA infection

For patients with cellulitis or erysipelas without systemic features who are at low risk of methicillin-resistant Staphylococcus aureus (MRSA) infection (see Risk factors for infection with methicillin-resistant Staphylococcus aureus), use:

1dicloxacillin 500 mg (child: 12.5 mg/kg up to 500 mg) orally, 6-hourly. For dosage adjustment in adults with kidney impairment, see dicloxacillin dosage adjustment. See advice on patient review, and modification and duration of therapy dicloxacillin dicloxacillin dicloxacillin

1flucloxacillin 500 mg (child: 12.5 mg/kg up to 500 mg) orally, 6-hourly. For dosage adjustment in adults with kidney impairment, see flucloxacillin oral dosage adjustment. See advice on patient review, and modification and duration of therapy. flucloxacillin flucloxacillin flucloxacillin

If Streptococcus pyogenes (group A streptococcus [GAS]) or other beta-haemolytic streptococci are suspected based on clinical presentation (eg nonpurulent, recurrent cellulitis), use:

phenoxymethylpenicillin 500 mg (child: 12.5 mg/kg up to 500 mg) orally, 6-hourly. See advice on patient review, and modification and duration of therapy. phenoxymethylpenicillin phenoxymethylpenicillin phenoxymethylpenicillin

Cefalexin is often preferred to dicloxacillin or flucloxacillin in children because the liquid formulation is better tolerated. It can also be used for patients who have had a nonsevere (immediate or delayed) hypersensitivity reaction to a penicillin¹. Use:

1cefalexin 500 mg (child: 12.5 mg/kg up to 500 mg) orally, 6-hourly. For dosage adjustment in adults with kidney impairment, see cefalexin dosage adjustment. See advice on patient review, and modification and duration of therapy cefalexin cefalexin cefalexin

OR if adherence to a 6-hourly regimen is unlikely in a child

1cefalexin 20 mg/kg up to 750 mg orally, 8-hourly². See advice on patient review, and modification and duration of therapy. cefalexin

For patients who have had a severe (immediate or delayed)³ hypersensitivity reaction to a penicillin, use trimethoprim+sulfamethoxazole or clindamycin (see Patients with cellulitis or erysipelas without systemic features who are at increased risk of MRSA infection for dosages).

¹ Cefalexin may be used in patients who have had a nonsevere (immediate or delayed) reaction to amoxicillin or ampicillin. However, because cross-reactivity between these drugs is possible, consideration should be given to the extent of the reaction, patient acceptability, and the suitability of non–beta-lactam options.Return

² Unpublished pharmacokinetic and pharmacodynamic modelling data for cefalexin show similar levels of target attainment with the 6- and 8-hourly regimens above. It is the consensus view of the Antibiotic Expert Group that either regimen can be used for children.Return

³ Severe immediate hypersensitivity reactions include anaphylaxis, compromised airway, airway angioedema, hypotension and collapse. Severe delayed hypersensitivity reactions include cutaneous adverse drug reactions (eg drug rash with eosinophilia and systemic symptoms [DRESS], Stevens–Johnson syndrome/toxic epidermal necrolysis [SJS/TEN], severe blistering or desquamative rash), and significant internal organ involvement (eg acute interstitial nephritis).Return