Drug interactions
Nortriptyline + Trihexyphenidyl
Severity: Moderate
Nortriptyline and Trihexyphenidyl: 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 activity, so combined use may cause marked dry mouth, constipation, urinary retention, blurred vision and confusion. Older patients and those with glaucoma or prostatic enlargement are at higher risk.
What this interaction means in plain words
Nortriptyline and Trihexyphenidyl 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.
Nortriptyline belongs to Central Nervous System; Trihexyphenidyl belongs to Central Nervous System.
Why it happens
Additive antimuscarinic effects.
What to do
Monitor for anticholinergic toxicity, especially cognitive effects and urinary retention. Use the lowest effective doses or choose a less anticholinergic antidepressant.
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 Nortriptyline
- Disopyramide + Nortriptyline Contraindicated
- Dofetilide + Nortriptyline Contraindicated
- Dronedarone + Nortriptyline Contraindicated
- Ibutilide + Nortriptyline Contraindicated
- Isocarboxazid + Nortriptyline Contraindicated
- Methylene blue + Nortriptyline Contraindicated
Other interactions of Trihexyphenidyl
Frequently asked questions
Can I take Nortriptyline with Trihexyphenidyl?
MediHelp rates the interaction as moderate. Nortriptyline and Trihexyphenidyl 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 activity, so combined use may cause marked dry mouth, constipation, urinary retention, blurred vision and confusion. Older patients and those with glaucoma or prostatic enlargement are at higher risk.
How serious is the interaction between Nortriptyline and Trihexyphenidyl?
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, especially cognitive effects and urinary retention. Use the lowest effective doses or choose a less anticholinergic antidepressant.
What other medicines interact with Nortriptyline?
MediHelp also lists interactions of Nortriptyline with, for example, Disopyramide, Dofetilide, Dronedarone. The full list is on the Nortriptyline page.
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