Co-amoxiclav
General Information
A penicillin and beta-lactamase inhibitor. Do NOT use if patient is allergic to penicillin.
Amoxicillin and clavulanic acid
Formulary antimicrobial: Use in accordance with Trust guidelines
AWaRe antibiotic classification: 'Watch'. Use as per guidelines. All other indications to be discussed with Micro/ID.
Standard dose
| Oral co-amoxiclav | Intravenous co-amoxiclav | |
| Standard dose |
625mg TDS (Amoxicillin 500mg and clavulanic acid 125mg) |
1.2g TDS (Amoxicillin 1000mg and clavulanic acid 200mg) |
Obesity
No dose adjustment required.
Renal and Hepatic impairment
Renal impairment
| eGFR (mL/min/1.73m2) |
Oral co-amoxiclav dose |
Intravenous co-amoxiclav dose |
| 30 or more |
No adjustment |
No adjustment |
| Less than 30 | 1.2g bd | |
| HD/ HDF/ High Flux/ PD | 1.2g bd. Dialysed |
Note: The reference for this dosing information is Renal Drug Database and dosing is different to those in BNF and Summary of Product Characteristics.
Hepatic impairment
- Contraindicated in history of jaundice/hepatic impairment due to amoxicillin/clavulanic acid
- Dose with caution in hepatic impairment and monitor hepatic function at regular intervals.
- Signs and symptoms of hepatic injury can occur either during or shortly after the use of co-amoxiclav but in some cases may not become apparent until several weeks after treatment has ceased.
- Hepatic events have been reported predominantly in males and elderly patients and may be associated with prolonged treatment.
Notable Interactions
Methotrexate: Amoxicillin can reduce excretion of methotrexate (increased risk of toxicity).
Mycophenolate: Co-amoxiclav can reduce serum concentrations of mycophenolate. Dose adjustments are not routinely recommended but close monitoring during, and shortly after, concurrent use is advisable.
Vitamin K antagonists: Appropriate monitoring should be undertaken. It would be prudent to monitor coagulation status within 3 days of starting or stopping a penicillin.
This is not a complete list. Please see the BNF, Summary of Product Characteristics or speak to a pharmacist.
Pregnancy and breastfeeding
Pregnancy
Generally safe to use in pregnancy. Co-amoxiclav should not be used in patients with pre-labour premature rupture of the membranes owing to a possible increased risk of necrotising enterocolitis in the neonate.
Breastfeeding
Trace amounts in breast milk, but appropriate to use. Monitor infant for gastro-intestinal disturbances and oral candida infection, especially if used for prolonged periods or in high doses, although these effects are unlikely to occur. There is also a theoretical risk of hypersensitivity.
Additional information
Co-amoxiclav 1.2g IV contains 62.9 mg (2.7 mmol) of sodium per vial, equivalent to 3.145% of the WHO recommended maximum daily intake of 2 g sodium for an adult.
References
- Co-amoxiclav 500mg/125mg film-coated Tablets [online]. Manufacturer - Brown & Burk UK Ltd – last updated: 2022 Oct 27. Accessed via: www.emc.medicines.org.uk [Accessed 2022 Nov 29].
- Co-amoxiclav 1000/200 mg Powder for Solution for Injection/Infusion [online]. Manufacturer - Esteve Pharmaceuticals (formerly Intrapharm Laboratories) – last updated: 2022 Jun 21. Accessed via: www.emc.medicines.org.uk [Accessed 2022 Nov 29].
- The Renal Drug Database. Co-amoxiclav - last updated: 2019 Sep 9. Accessed via: https://renaldrugdatabase.com [Accessed16/9/23].
- Specialist Pharmacy Service – Lactation Safety Information: Co-amoxiclav – last updated 2020 July 30. Accessed via: https://www.sps.nhs.uk/medicines/co-amoxiclav/ [Accessed 16/9/23].
- UK Teratology Information Service - USE OF PENICILLINS IN PREGNANCY – last updated January 2019. Accessed via: https://www.medicinesinpregnancy.org/ [Accessed 16/9/23]