Flucloxacillin (Burns — Wound Infection)

How it works

It inhibits bacterial cell-wall synthesis by binding penicillin-binding proteins, and its acyl side chain resists staphylococcal beta-lactamase, retaining activity against most meticillin-sensitive S. aureus.

Prescribing in practice

• Cholestatic hepatitis and jaundice can occur, sometimes weeks after stopping, and risk rises with prolonged courses and increasing age — counsel and avoid unnecessarily long treatment.
• It has no useful activity against MRSA or Gram-negative organisms, so review wound cultures and broaden or switch if these are isolated.
• Avoid in patients with a history of penicillin hypersensitivity and take care to distinguish true allergy from non-immune reactions before labelling.

Monitoring

Monitor clinical response and the wound, and check liver function during prolonged or high-intensity courses given the risk of cholestatic injury.

Counselling the patient

• Take on an empty stomach, well before food, as absorption is reduced by food.
• Report yellowing of the skin or eyes, dark urine or pale stools, even after the course has finished.

Evidence & guidelines

Flucloxacillin is the standard first-line agent for staphylococcal soft-tissue infection in UK practice, with MHRA advice highlighting the risk of cholestatic hepatic reactions.