Please note: This is for information only.

Refer to local guidelines for treatment recommendations


Co-Amoxiclav = amoxicillin + clavulanic acid.


  • A penicillin

Clavulanic acid:

  • A ß-lactamase inhibitor which irreversibly inactivates the enzyme.
  • ‘Protects’ the penicillin from the destructive effects of ß-lactamase


  • The combination is bactericidal.
  • Usual adult dose: 375mg – 625mg orally or 1.2g iv three times a day
  • Dose adjustment necessary if renal impairment
  • May cause hepatic dysfunction, including cholestatic janudice. The British National Formulary (BNF) from July 2017 states "Cholestatic jaundice can occur either during or shortly after the use of co-amoxiclav. An epidemiological study has shown that the risk of acute liver toxicity was about 6 times greater with co-amoxiclav than with amoxicillin. Cholestatic jaundice is more common in patients above the age of 65 years and in men; these reactions have only rarely been reported in children. Jaundice is usually self-limiting and very rarely fatal. The duration of treatment should be appropriate to the indication and should not usually exceed 14 days." The manufacturer of co-amoxiclav advises for patients with hepatic impairment, "to dose with caution and monitor hepatic function at regular intervals". They also state that the use of the drug is "contraindicated in patients with a history of jaundice/hepatic impairment due to co-amoxiclav".
  • Moderate risk of Clostridium difficile antibiotic-associated diarrhoea if prescribed for elderly in-patients

Main indications:

  • Bites: animal or human
  • UTI
  • Acute Bronchitis
  • Diabetic ulcers
  • Biliary Sepsis
  • Surgical prophylaxis

Active against most strains of:

  • Staphylococcus aureus (not MRSA)
  • Haemolytic streptococci
  • Streptococcus pneumoniae
  • Haemophilus influenzae
  • Escherichia coli
  • Anaerobes
  • Enterococcus faecalis
  • Moraxella
  • Klebsiella

Not active against most strains of:

  • MRSA
  • Clostridium difficile
  • Pseudomonas aeruginosa
  • Enterococcus faecium (amoxicillin –resistant)