Drug interactions
Amitriptyline + Orphenadrin
Severity: Moderate
Amitriptyline and Orphenadrin: 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 anticholinergic and sedative properties, so combined use can cause dry mouth, constipation, urinary retention, blurred vision, tachycardia, confusion and marked drowsiness. Older patients and those with glaucoma or prostatic enlargement are at greater risk.
What this interaction means in plain words
Amitriptyline and Orphenadrin 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.
Amitriptyline belongs to Central Nervous System; Orphenadrin belongs to Musculoskeletal.
Why it happens
Additive antimuscarinic and CNS depressant effects.
What to do
Monitor for anticholinergic toxicity and sedation, and use the lowest effective doses. Consider an alternative muscle relaxant in elderly patients or those with narrow-angle 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 Orphenadrin
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 Orphenadrin?
MediHelp rates the interaction as moderate. Amitriptyline and Orphenadrin 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 anticholinergic and sedative properties, so combined use can cause dry mouth, constipation, urinary retention, blurred vision, tachycardia, confusion and marked drowsiness. Older patients and those with glaucoma or prostatic enlargement are at greater risk.
How serious is the interaction between Amitriptyline and Orphenadrin?
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. Consider an alternative muscle relaxant in elderly patients or those with narrow-angle glaucoma or urinary retention.
What other medicines interact with Orphenadrin?
MediHelp also lists interactions of Orphenadrin with, for example, Alfentanil, Amobarbital, Benzhydrocodone / acetaminophen. The full list is on the Orphenadrin page.
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