Executive summary
- Do not prescribe antibiotics for leg ulcers unless there are clear clinical signs of infection (increased pain, erythema, warmth, swelling, purulent discharge, malodour, systemic features).
- First-line oral therapy targets staph/strep; tailor to allergies and severity.
- Reassess at 2–3 days if not improving or rapidly worsening; consider microbiology sampling after cleaning if deteriorating.
Adult antibiotic choices (Table 1 – practical list)
- First-choice oral: Flucloxacillin 500 mg to 1 g QDS for 7 days.
- Penicillin allergy / flucloxacillin unsuitable:
- Doxycycline 200 mg day 1, then 100 mg OD (may increase to 200 mg daily) for 7 days total.
- Clarithromycin 500 mg BD for 7 days.
- Erythromycin (pregnancy): 500 mg QDS for 7 days.
- Second-choice (guided by results): Co-amoxiclav 500/125 mg TDS for 7 days.
- Penicillin allergy second-choice: Co-trimoxazole 960 mg BD for 7 days (monitor per BNF; local policies apply).
When to culture / refer
- Culture: consider a sample (after cleaning) if worsening, not improving as expected, or recurrent/resistant patterns.
- Refer to hospital: systemic illness, severe pain out of proportion, suspected osteomyelitis/necrotising infection, sepsis features.
- Seek specialist advice: diabetes/immunosuppression, lymphangitis, spreading infection not responding to oral therapy, inability to take oral antibiotics.
Transparency
This page is an educational, clinician-written summary of publicly available NICE guidance intended for trained healthcare professionals. It uses original wording (not copied text) and should be used alongside the full NICE source, local pathways, and clinical judgement. Doses provided are for general reference; always check the BNF/SPC.