Drug interactions
Chlorpromazine + Memantine-donepezil
Severity: Major
Chlorpromazine and Memantine-donepezil: major 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
Chlorpromazine prolongs the QT interval, and donepezil carries a recognized risk of QT prolongation, torsades de pointes and bradycardia. Combined use increases the chance of serious ventricular arrhythmia, particularly in older patients with dementia who often have other risk factors.
What this interaction means in plain words
Chlorpromazine and Memantine-donepezil can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Chlorpromazine belongs to Central Nervous System; Memantine-donepezil belongs to Central Nervous System.
Why it happens
Additive pharmacodynamic QT prolongation, with donepezil adding vagotonic bradycardia.
What to do
Avoid the combination where possible and choose an antipsychotic with lower QT liability. If it is needed, obtain a baseline and follow-up ECG and correct potassium and magnesium.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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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 Chlorpromazine
- Chlorpromazine + Dofetilide Contraindicated
- Chlorpromazine + Dronedarone Contraindicated
- Chlorpromazine + Droperidol Contraindicated
- Chlorpromazine + Ibutilide Contraindicated
- Chlorpromazine + Metrizamide Contraindicated
- Chlorpromazine + Panobinostat Contraindicated
Frequently asked questions
Can I take Chlorpromazine with Memantine-donepezil?
MediHelp rates the interaction as major. Chlorpromazine and Memantine-donepezil can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Chlorpromazine prolongs the QT interval, and donepezil carries a recognized risk of QT prolongation, torsades de pointes and bradycardia. Combined use increases the chance of serious ventricular arrhythmia, particularly in older patients with dementia who often have other risk factors.
How serious is the interaction between Chlorpromazine and Memantine-donepezil?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination where possible and choose an antipsychotic with lower QT liability. If it is needed, obtain a baseline and follow-up ECG and correct potassium and magnesium.
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.
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