Drug interactions
Chlorpromazine + Marijuana
Severity: Moderate
Chlorpromazine 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
Cannabis and chlorpromazine both depress the central nervous system, so drowsiness, impaired psychomotor performance and dizziness may be greater than with either alone. Cannabis can also cause tachycardia and orthostatic hypotension, which may add to the hypotensive effect of chlorpromazine.
What this interaction means in plain words
Chlorpromazine 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
Additive CNS depression and additive cardiovascular effects (orthostatic hypotension, tachycardia).
What to do
Advise patients to avoid cannabis or limit use and to avoid driving or operating machinery. Monitor sedation and orthostatic blood pressure.
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 Chlorpromazine
- Chlorpromazine + Dofetilide Contraindicated
- Chlorpromazine + Dronedarone Contraindicated
- Chlorpromazine + Droperidol Contraindicated
- Chlorpromazine + Ibutilide Contraindicated
- Chlorpromazine + Metrizamide Contraindicated
- Chlorpromazine + Panobinostat Contraindicated
Frequently asked questions
Can I take Chlorpromazine with Marijuana?
MediHelp rates the interaction as moderate. Chlorpromazine 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. Cannabis and chlorpromazine both depress the central nervous system, so drowsiness, impaired psychomotor performance and dizziness may be greater than with either alone. Cannabis can also cause tachycardia and orthostatic hypotension, which may add to the hypotensive effect of chlorpromazine.
How serious is the interaction between Chlorpromazine 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: Advise patients to avoid cannabis or limit use and to avoid driving or operating machinery. Monitor sedation and orthostatic blood pressure.
What other medicines interact with Chlorpromazine?
MediHelp also lists interactions of Chlorpromazine with, for example, Dofetilide, Dronedarone, Droperidol. The full list is on the Chlorpromazine page.
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