Drug interactions
Carbamazepine + Marijuana
Severity: Moderate
Carbamazepine and Marijuana: 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
Carbamazepine may lower THC and other cannabinoid exposure, while cannabidiol may raise carbamazepine levels. Additive sedation can also occur.
What this interaction means in plain words
Carbamazepine and Marijuana 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
Carbamazepine induces CYP3A4 which metabolises cannabinoids, while cannabidiol inhibits CYP enzymes that metabolise carbamazepine, with additive CNS depression.
What to do
Monitor carbamazepine levels and signs of toxicity such as dizziness, ataxia and diplopia if cannabinoid use is regular. Counsel the patient about sedation and impaired driving.
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 Marijuana?
MediHelp rates the interaction as moderate. Carbamazepine and Marijuana 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. Carbamazepine may lower THC and other cannabinoid exposure, while cannabidiol may raise carbamazepine levels. Additive sedation can also occur.
How serious is the interaction between Carbamazepine and Marijuana?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor carbamazepine levels and signs of toxicity such as dizziness, ataxia and diplopia if cannabinoid use is regular. Counsel the patient about sedation and impaired driving.
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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