Drug interactions
Belladonna and opium + Memantine-donepezil
Severity: Moderate
Belladonna and opium and Memantine-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 opposes the cholinergic effect of donepezil, and the opium component adds sedation and confusion, which can worsen cognition and falls risk in older dementia patients.
What this interaction means in plain words
Belladonna and opium and Memantine-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 additive CNS depression from the opioid.
What to do
Avoid use where possible in patients with dementia, and monitor cognition, sedation and bowel function if therapy is required.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Belladonna and opium and Memantine-donepezil, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Memantine-donepezil
- Dronedarone + Memantine-donepezil Contraindicated
- Memantine-donepezil + Thioridazine Contraindicated
- Amantadine + Memantine-donepezil Major
- Amiodarone + Memantine-donepezil Major
- Amisulpride + Memantine-donepezil Major
- Amitriptyline + Memantine-donepezil Major
Frequently asked questions
Can I take Belladonna and opium with Memantine-donepezil?
MediHelp rates the interaction as moderate. Belladonna and opium and Memantine-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 opposes the cholinergic effect of donepezil, and the opium component adds sedation and confusion, which can worsen cognition and falls risk in older dementia patients.
How serious is the interaction between Belladonna and opium and Memantine-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 use where possible in patients with dementia, and monitor cognition, sedation and bowel function if therapy is required.
What other medicines interact with Memantine-donepezil?
MediHelp also lists interactions of Memantine-donepezil with, for example, Dronedarone, Thioridazine, Amantadine. The full list is on the Memantine-donepezil page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
