Drug interactions
Belladonna alkaloids + Donepezil
Severity: Moderate
Belladonna alkaloids and Donepezil: 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
Belladonna alkaloids such as atropine and hyoscyamine block muscarinic receptors and oppose donepezil's cholinergic action. This may reduce the cognitive benefit of donepezil and may worsen confusion in dementia.
What this interaction means in plain words
Belladonna alkaloids and Donepezil 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
Pharmacodynamic antagonism of acetylcholine by muscarinic receptor blockade.
What to do
Avoid anticholinergic belladonna products in patients with dementia taking donepezil when an alternative exists. If used, monitor cognition and treatment 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 Donepezil
- Donepezil + Dronedarone Contraindicated
- Donepezil + Pimozide Contraindicated
- Donepezil + Thioridazine Contraindicated
- Donepezil + Vandetanib Contraindicated
- Amiodarone + Donepezil Major
- Amisulpride + Donepezil Major
Frequently asked questions
Can I take Belladonna alkaloids with Donepezil?
MediHelp rates the interaction as moderate. Belladonna alkaloids and Donepezil 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. Belladonna alkaloids such as atropine and hyoscyamine block muscarinic receptors and oppose donepezil's cholinergic action. This may reduce the cognitive benefit of donepezil and may worsen confusion in dementia.
How serious is the interaction between Belladonna alkaloids and Donepezil?
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 anticholinergic belladonna products in patients with dementia taking donepezil when an alternative exists. If used, monitor cognition and treatment response.
What other medicines interact with Donepezil?
MediHelp also lists interactions of Donepezil with, for example, Dronedarone, Pimozide, Thioridazine. The full list is on the Donepezil page.
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