Drug interactions
Clemastine + Perphenazine
Severity: Moderate
Clemastine 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
Both drugs are sedating and anticholinergic, so combined use may lead to marked drowsiness, impaired coordination, dry mouth and urinary retention. Elderly patients are especially vulnerable.
What this interaction means in plain words
Clemastine 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.
Clemastine belongs to Respiratory; Perphenazine belongs to Central Nervous System.
Why it happens
Additive CNS depression and muscarinic blockade.
What to do
Counsel on drowsiness and avoiding alcohol or driving, and monitor for anticholinergic toxicity. Substitute a non-sedating antihistamine where possible.
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
Other interactions of Clemastine
Frequently asked questions
Can I take Clemastine with Perphenazine?
MediHelp rates the interaction as moderate. Clemastine 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. Both drugs are sedating and anticholinergic, so combined use may lead to marked drowsiness, impaired coordination, dry mouth and urinary retention. Elderly patients are especially vulnerable.
How serious is the interaction between Clemastine 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 on drowsiness and avoiding alcohol or driving, and monitor for anticholinergic toxicity. Substitute a non-sedating antihistamine where possible.
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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