Drug interactions
Cilostazol + Diltiazem
Severity: Moderate
Cilostazol and Diltiazem: 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 increases cilostazol exposure, which may cause headache, tachycardia, palpitations and diarrhoea. Cilostazol is contraindicated in heart failure so excess exposure matters.
What this interaction means in plain words
Cilostazol and Diltiazem 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.
Cilostazol belongs to Cardiovascular; Diltiazem belongs to Cardiovascular.
Why it happens
Diltiazem inhibits CYP3A4-mediated metabolism of cilostazol.
What to do
Reduce the cilostazol dose to 50 mg twice daily while diltiazem is used. Monitor heart rate and tolerability.
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 Cilostazol
Frequently asked questions
Can I take Cilostazol with Diltiazem?
MediHelp rates the interaction as moderate. Cilostazol and Diltiazem 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 increases cilostazol exposure, which may cause headache, tachycardia, palpitations and diarrhoea. Cilostazol is contraindicated in heart failure so excess exposure matters.
How serious is the interaction between Cilostazol and Diltiazem?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Reduce the cilostazol dose to 50 mg twice daily while diltiazem is used. Monitor heart rate and tolerability.
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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