Drug interactions
Galantamine + Trihexyphenidyl
Severity: Moderate
Galantamine 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
Galantamine increases acetylcholine availability while trihexyphenidyl blocks muscarinic receptors, so each can reduce the other's effect. The result may be diminished cognitive benefit and unpredictable motor symptom control.
What this interaction means in plain words
Galantamine 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.
Galantamine belongs to Central Nervous System; Trihexyphenidyl belongs to Central Nervous System.
Why it happens
Pharmacodynamic antagonism between a cholinesterase inhibitor and a muscarinic antagonist.
What to do
Avoid the combination if possible, and review the ongoing need for the anticholinergic. If both are needed, monitor cognitive and motor response.
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 Trihexyphenidyl
Other interactions of Galantamine
- Galantamine + Memantine-donepezil Major
- Galantamine + Physostigmine Major
- Galantamine + Ponesimod Major
- Galantamine + Rivastigmine Major
- Amifampridine + Galantamine Moderate
- Amiodarone + Galantamine Moderate
Frequently asked questions
Can I take Galantamine with Trihexyphenidyl?
MediHelp rates the interaction as moderate. Galantamine 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. Galantamine increases acetylcholine availability while trihexyphenidyl blocks muscarinic receptors, so each can reduce the other's effect. The result may be diminished cognitive benefit and unpredictable motor symptom control.
How serious is the interaction between Galantamine 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: Avoid the combination if possible, and review the ongoing need for the anticholinergic. If both are needed, monitor cognitive and motor response.
What other medicines interact with Trihexyphenidyl?
MediHelp also lists interactions of Trihexyphenidyl with, for example, Orphenadrin, Oxybutynin, Scopolamine. The full list is on the Trihexyphenidyl page.
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