Co-amoxiclav (Open Fracture Antibiotic Prophylaxis)

How it works

Amoxicillin inhibits bacterial cell-wall synthesis via penicillin-binding proteins, while clavulanic acid irreversibly inhibits many bacterial beta-lactamases, restoring activity against beta-lactamase-producing staphylococci and Gram-negative organisms relevant to wound contamination.

Prescribing in practice

• Do not use in patients with previous penicillin anaphylaxis or with a history of co-amoxiclav-associated jaundice or hepatic dysfunction; verify allergy status urgently in the trauma setting and use an alternative regimen if needed.
• Give early after open-fracture injury and alongside thorough wound management and tetanus prophylaxis, as antibiotics complement but do not replace timely surgical debridement.
• Co-amoxiclav can cause cholestatic jaundice (more often in older men and with longer courses) and the dose frequency needs adjustment in renal impairment — follow local open-fracture and the SPC guidance.

Monitoring

Monitor the wound and systemic response, observe for hypersensitivity, and check liver function if therapy is prolonged or jaundice is suspected.

Counselling the patient

• Tell staff about any penicillin allergy or previous reaction to this antibiotic before it is given.
• Report yellowing of the skin or eyes, dark urine, rash or breathing difficulty.
• Understand that the antibiotic works alongside, and does not replace, surgical cleaning of the wound and tetanus cover.

Evidence & guidelines

NICE and BOAST open-fracture standards recommend prompt intravenous antibiotics after injury together with timely debridement and stabilisation to reduce deep infection.