Drug interactions
Marijuana + Perphenazine
Severity: Moderate
Marijuana and Perphenazine: 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 causes sedation, impaired cognition and tachycardia, and can add to the sedative effects of perphenazine. Cannabis may also worsen psychosis, opposing the antipsychotic's therapeutic effect.
What this interaction means in plain words
Marijuana and Perphenazine 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 central nervous system depression, plus cannabinoid-related psychotomimetic effects opposing antipsychotic action.
What to do
Counsel patients to avoid cannabis, particularly those with psychotic disorders. Monitor for sedation, orthostatic hypotension and psychiatric relapse.
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 Perphenazine
- Ibutilide + Perphenazine Contraindicated
- Perphenazine + Pimozide Contraindicated
- Perphenazine + Thioridazine Contraindicated
- Adagrasib + Perphenazine Major
- Alfentanil + Perphenazine Major
- Amiodarone + Perphenazine Major
Frequently asked questions
Can I take Marijuana with Perphenazine?
MediHelp rates the interaction as moderate. Marijuana and Perphenazine 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 causes sedation, impaired cognition and tachycardia, and can add to the sedative effects of perphenazine. Cannabis may also worsen psychosis, opposing the antipsychotic's therapeutic effect.
How serious is the interaction between Marijuana and Perphenazine?
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 to avoid cannabis, particularly those with psychotic disorders. Monitor for sedation, orthostatic hypotension and psychiatric relapse.
What other medicines interact with Perphenazine?
MediHelp also lists interactions of Perphenazine with, for example, Ibutilide, Pimozide, Thioridazine. The full list is on the Perphenazine page.
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