Drug interactions
Belladonna and opium + Donepezil
Severity: Moderate
Belladonna and opium 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
The belladonna component is antimuscarinic and opposes donepezil, while the opium component adds sedation and constipation. Together they may reduce donepezil's effect and worsen confusion in older patients.
What this interaction means in plain words
Belladonna and opium 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
Antimuscarinic antagonism of cholinesterase inhibition, plus opioid CNS depression.
What to do
Avoid if possible in patients with dementia; use another agent for the indication. If needed, monitor cognition, sedation and bowel function.
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 and opium with Donepezil?
MediHelp rates the interaction as moderate. Belladonna and opium 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. The belladonna component is antimuscarinic and opposes donepezil, while the opium component adds sedation and constipation. Together they may reduce donepezil's effect and worsen confusion in older patients.
How serious is the interaction between Belladonna and opium 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 if possible in patients with dementia; use another agent for the indication. If needed, monitor cognition, sedation and bowel function.
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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