Drug interactions
Carbamazepine + Grapefruit
Severity: Moderate
Carbamazepine and Grapefruit: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Grapefruit juice can raise carbamazepine concentrations, potentially causing dizziness, ataxia, diplopia and nausea. The effect varies between patients and is greater with regular intake.
What this interaction means in plain words
Carbamazepine and Grapefruit can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Grapefruit components inhibit intestinal CYP3A4, reducing first-pass metabolism of carbamazepine.
What to do
Advise patients to avoid grapefruit and its juice during carbamazepine treatment. If intake is consistent, monitor carbamazepine levels.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Carbamazepine
- Artemether / lumefantrine + Carbamazepine Contraindicated
- Cabotegravir + Carbamazepine Contraindicated
- Carbamazepine + Delamanid Contraindicated
- Carbamazepine + Dienogest / estradiol valerate Contraindicated
- Carbamazepine + Doravirine Contraindicated
- Carbamazepine + Elbasvir / grazoprevir Contraindicated
Frequently asked questions
Can I take Carbamazepine with Grapefruit?
MediHelp rates the interaction as moderate. Carbamazepine and Grapefruit can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Grapefruit juice can raise carbamazepine concentrations, potentially causing dizziness, ataxia, diplopia and nausea. The effect varies between patients and is greater with regular intake.
How serious is the interaction between Carbamazepine and Grapefruit?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise patients to avoid grapefruit and its juice during carbamazepine treatment. If intake is consistent, monitor carbamazepine levels.
What other medicines interact with Carbamazepine?
MediHelp also lists interactions of Carbamazepine with, for example, Artemether / lumefantrine, Cabotegravir, Delamanid. The full list is on the Carbamazepine page.
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