Drug interactions
Marijuana + Methadone
Severity: Moderate
Marijuana and Methadone: 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
Cannabis has additive sedative and psychomotor effects with methadone. Cannabinoids may also have minor effects on CYP enzymes, though a clinically significant change in methadone levels is not established.
What this interaction means in plain words
Marijuana and Methadone 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
Additive CNS depression, with weak and unconfirmed CYP3A4 inhibition by cannabinoids.
What to do
Counsel patients about additive drowsiness and impaired driving. Monitor sedation and respiratory function, particularly with edible or high-potency products.
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 Methadone
- Alvimopan + Methadone Contraindicated
- Calcium / magnesium / potassium / sodium oxybates + Methadone Contraindicated
- Droperidol + Methadone Contraindicated
- Ibutilide + Methadone Contraindicated
- Isocarboxazid + Methadone Contraindicated
- Lefamulin + Methadone Contraindicated
Frequently asked questions
Can I take Marijuana with Methadone?
MediHelp rates the interaction as moderate. Marijuana and Methadone 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. Cannabis has additive sedative and psychomotor effects with methadone. Cannabinoids may also have minor effects on CYP enzymes, though a clinically significant change in methadone levels is not established.
How serious is the interaction between Marijuana and Methadone?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Counsel patients about additive drowsiness and impaired driving. Monitor sedation and respiratory function, particularly with edible or high-potency products.
What other medicines interact with Methadone?
MediHelp also lists interactions of Methadone with, for example, Alvimopan, Calcium / magnesium / potassium / sodium oxybates, Droperidol. The full list is on the Methadone page.
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