Leg Ulcers and recurrent cellulitis

Doses are oral and for adults unless otherwise stated. Visit the Health Products Regulatory Board website or the printed Irish Medicines Formulary for drug SPCs, dosage, contraindications, interactions, or IMF/BNF/BNFC/MIMS. See guidance on dosing in children for quick reference dosage/weight guide.

Letters indicate strength of evidence range from A+ (systematic review) to D (informal opinion). Statins can interact with some antibiotics and increase the risk of rhabdomyolysis. Amiodarone and drugs which prolong the QT interval can interact with many antibiotics. Many antibiotics increase the risk of bleeding with anticoagulants. Please refer to our Drug Interactions Table for further information.

Comments from Expert Advisory Committee

Antibiotics do not improve healing unless active infection.A+ Culture swabs and antibiotics are only indicated if there is evidence of clinical cellulitis; increased pain; enlarging ulcer or pyrexia.

Review antibiotics after culture results.

Refer for specialist opinion if severe infection

  • Is it cellulitis?
  • Bilateral cellulitis is uncommon.
  • Is it chronic changes of venous stasis and chronic ulceration?
  • Don’t swab unless atypical organisms suspected. Colonisation is likely in leg ulcers.
  • 2 or more episodes of proven cellulitis may benefit form low dose prophylactic penicillin (in non-penecillin allergic patients).
  • PATCH I & II clinical trials: 250mgs of penecillin 6-12 months reduced episodes of cellulitis.
  • Are they suitable for compression?
  • Treat tinea pedis or candida infection with topical terbenifine or miconazole respectively.


  • Thomas K, Crook A, Nunn AJ et al. Penecillin to prevent leg cellulitis NEJM 2013 368;18:1695-1703.
  • Thomas K, Crook A, Foster Ket al. Prophalactic antibiotics for the prevention of cellulitis (erysipelas) of the leg:results of the U.K. Dermatology Clinical Trials Network PATCH II trial. BJD 2012;166:169-78.


See guidance on dosing in children for quick reference dosage/weight guide.

Treatment Dose TX Duration
flucloxacillin 500 mg QDS 7 days and review
OR clarithromycin 500mg BD 7 days and review

Patient Information

We recommend patients use the website developed by HSE/ICGP/IPU partnership www.undertheweather.ie for tips on how to get better from common infections without using antibiotics, what you can do for yourself or a loved one and when to seek help.

Reviewed June 2016