Drug interactions
Orphenadrine + Perphenazine
Severity: Moderate
Orphenadrine 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 have anticholinergic and sedating properties. Combined use can cause excessive drowsiness, confusion, dry mouth, urinary retention, constipation and tachycardia, especially in older adults. Orphenadrine may also reduce the extrapyramidal symptoms caused by perphenazine.
What this interaction means in plain words
Orphenadrine 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 antimuscarinic and CNS depressant effects.
What to do
Monitor for anticholinergic toxicity and sedation, and use the lowest effective doses. Avoid or reduce the combination in elderly patients and those with glaucoma, urinary retention or cognitive impairment.
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 Orphenadrine with Perphenazine?
MediHelp rates the interaction as moderate. Orphenadrine 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 have anticholinergic and sedating properties. Combined use can cause excessive drowsiness, confusion, dry mouth, urinary retention, constipation and tachycardia, especially in older adults. Orphenadrine may also reduce the extrapyramidal symptoms caused by perphenazine.
How serious is the interaction between Orphenadrine 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: Monitor for anticholinergic toxicity and sedation, and use the lowest effective doses. Avoid or reduce the combination in elderly patients and those with glaucoma, urinary retention or cognitive impairment.
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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