Drug interactions
Amitriptyline + Orphenadrine
Severity: Moderate
Amitriptyline and Orphenadrine: 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 strong antimuscarinic activity and cause sedation, so combined use can produce marked anticholinergic toxicity. Effects include dry mouth, constipation, urinary retention, blurred vision, confusion, and tachycardia, especially in older patients.
What this interaction means in plain words
Amitriptyline and Orphenadrine 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 symptoms and cognitive impairment, and reduce doses where needed. Avoid in older adults and in patients with glaucoma or urinary retention.
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 Amitriptyline
- Amitriptyline + Isocarboxazid Contraindicated
- Amitriptyline + Methylene blue Contraindicated
- Amitriptyline + Phenelzine Contraindicated
- Amitriptyline + Pimozide Contraindicated
- Amitriptyline + Procarbazine Contraindicated
- Amitriptyline + Safinamide Contraindicated
Frequently asked questions
Can I take Amitriptyline with Orphenadrine?
MediHelp rates the interaction as moderate. Amitriptyline and Orphenadrine 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 strong antimuscarinic activity and cause sedation, so combined use can produce marked anticholinergic toxicity. Effects include dry mouth, constipation, urinary retention, blurred vision, confusion, and tachycardia, especially in older patients.
How serious is the interaction between Amitriptyline and Orphenadrine?
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 symptoms and cognitive impairment, and reduce doses where needed. Avoid in older adults and in patients with glaucoma or urinary retention.
What other medicines interact with Amitriptyline?
MediHelp also lists interactions of Amitriptyline with, for example, Isocarboxazid, Methylene blue, Phenelzine. The full list is on the Amitriptyline page.
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