Augmentin and grapefruit: a real interaction?
Grapefruit is famous as the juice that interacts with medications, and the warning is real for a number of drugs. Whether it matters specifically for Augmentin (Amoxicillin/Clavulanate) at 500/125mg, 875/125mg, 1000/62.5mg depends on whether the active ingredient Amoxicillin, Clavulanate is metabolised by CYP3A4 in the gut wall and how much that pathway contributes to first-pass metabolism.
The CYP3A4 mechanism
Grapefruit (and its juice) inhibits CYP3A4 enzymes in the gut wall, increasing the absorbed dose of medications metabolised by that enzyme. For drugs in the Antibiotics class that go through CYP3A4 first-pass metabolism, regular grapefruit consumption can raise plasma levels of Amoxicillin, Clavulanate by a clinically meaningful margin and amplify side effects.
What to do with Augmentin
According to the prescribing information for Amoxicillin, Clavulanate, if grapefruit is flagged as an interaction, the safest practice is to avoid grapefruit entirely or to discuss timing with the prescriber. Amoxicillin inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), but is hydrolysed by beta-lactamase enzymes produced by some resistant bacteria. A small occasional serving may be tolerable; daily large servings around the time of Augmentin dosing are not recommended at 500/125mg, 875/125mg, 1000/62.5mg.
Frequently asked questions
Can I eat grapefruit while on Augmentin? ▾
For some Antibiotics medications, grapefruit is best avoided or limited because of CYP3A4 inhibition. Whether Augmentin specifically is affected depends on Amoxicillin, Clavulanate; the prescribing information lists this. When in doubt, ask the pharmacist or check the patient leaflet.
How much grapefruit is too much with Augmentin? ▾
For drugs where the interaction matters, even modest daily grapefruit intake (one whole grapefruit or one large glass of juice) can shift drug levels noticeably. For Augmentin at 500/125mg, 875/125mg, 1000/62.5mg, individual tolerance varies; the cautious choice is to avoid grapefruit if any interaction is mentioned.
More on Augmentin
- With alcoholAugmentin and alcohol — is it safe to drink?
- With foodShould Augmentin be taken with food?
- Side effectsAugmentin side effects: common, rare and warning signs
- Dosage guideAugmentin dosage guide: how much to take and when
- OnsetHow fast does Augmentin start working?
- DurationHow long does Augmentin last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.