Drug interactions
Memantine-donepezil + Olanzapine
Severity: Moderate
Memantine-donepezil and Olanzapine: 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
Donepezil can prolong the QT interval and slow heart rate, and olanzapine has a small QT effect that is rarely significant. The combination may modestly increase arrhythmia risk in vulnerable patients. Olanzapine's anticholinergic activity may also blunt donepezil's benefit.
What this interaction means in plain words
Memantine-donepezil and Olanzapine 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.
Memantine-donepezil belongs to Central Nervous System; Olanzapine belongs to Central Nervous System.
Why it happens
Additive QT prolongation and opposing muscarinic effects.
What to do
Monitor ECG in patients with cardiac disease, bradycardia or electrolyte abnormalities. Use the lowest effective olanzapine dose and reassess cognition.
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 Memantine-donepezil and Olanzapine, 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
Other interactions of Olanzapine
Frequently asked questions
Can I take Memantine-donepezil with Olanzapine?
MediHelp rates the interaction as moderate. Memantine-donepezil and Olanzapine 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. Donepezil can prolong the QT interval and slow heart rate, and olanzapine has a small QT effect that is rarely significant. The combination may modestly increase arrhythmia risk in vulnerable patients. Olanzapine's anticholinergic activity may also blunt donepezil's benefit.
How serious is the interaction between Memantine-donepezil and Olanzapine?
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 ECG in patients with cardiac disease, bradycardia or electrolyte abnormalities. Use the lowest effective olanzapine dose and reassess cognition.
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.
