Drug interactions
Diltiazem + Galantamine
Severity: Moderate
Diltiazem and Galantamine: 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
Diltiazem may modestly raise galantamine exposure via CYP3A4 inhibition. Both drugs can slow heart rate, so additive bradycardia is also possible.
What this interaction means in plain words
Diltiazem and Galantamine 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.
Diltiazem belongs to Cardiovascular; Galantamine belongs to Central Nervous System.
Why it happens
CYP3A4 inhibition by diltiazem reduces galantamine clearance, with additive negative chronotropic effects.
What to do
Monitor heart rate and for cholinergic effects such as nausea, vomiting and syncope. Reduce the galantamine dose if these occur.
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 Diltiazem
- Diltiazem + Flibanserin Contraindicated
- Diltiazem + Ivabradine Contraindicated
- Diltiazem + Lomitapide Contraindicated
- Diltiazem + Lonafarnib Contraindicated
- Acebutolol + Diltiazem Major
- Alfentanil + Diltiazem Major
Other interactions of Galantamine
- Galantamine + Memantine-donepezil Major
- Galantamine + Physostigmine Major
- Galantamine + Ponesimod Major
- Galantamine + Rivastigmine Major
- Amifampridine + Galantamine Moderate
- Amiodarone + Galantamine Moderate
Frequently asked questions
Can I take Diltiazem with Galantamine?
MediHelp rates the interaction as moderate. Diltiazem and Galantamine 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. Diltiazem may modestly raise galantamine exposure via CYP3A4 inhibition. Both drugs can slow heart rate, so additive bradycardia is also possible.
How serious is the interaction between Diltiazem and Galantamine?
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 heart rate and for cholinergic effects such as nausea, vomiting and syncope. Reduce the galantamine dose if these occur.
What other medicines interact with Diltiazem?
MediHelp also lists interactions of Diltiazem with, for example, Flibanserin, Ivabradine, Lomitapide. The full list is on the Diltiazem page.
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