Drug interactions
Diltiazem + Felodipine
Severity: Moderate
Diltiazem and Felodipine: 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 inhibits CYP3A4 and raises felodipine exposure, increasing vasodilatory effects such as hypotension, flushing, headache and peripheral edema. Additive calcium channel blockade also occurs.
What this interaction means in plain words
Diltiazem and Felodipine 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; Felodipine belongs to Cardiovascular.
Why it happens
Diltiazem inhibits intestinal and hepatic CYP3A4, reducing felodipine clearance, with additive pharmacodynamic calcium channel blockade.
What to do
Avoid routine combination of two calcium channel blockers; if used, start with a low felodipine dose and monitor blood pressure, heart rate and edema.
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 Felodipine
- Felodipine + Itraconazole Contraindicated
- Aldesleukin + Felodipine Major
- Amifostine + Felodipine Major
- Apalutamide + Felodipine Major
- Atazanavir + Felodipine Major
- Carbamazepine + Felodipine Major
Other interactions of Diltiazem
- Diltiazem + Flibanserin Contraindicated
- Diltiazem + Ivabradine Contraindicated
- Diltiazem + Lomitapide Contraindicated
- Diltiazem + Lonafarnib Contraindicated
- Acebutolol + Diltiazem Major
- Alfentanil + Diltiazem Major
Frequently asked questions
Can I take Diltiazem with Felodipine?
MediHelp rates the interaction as moderate. Diltiazem and Felodipine 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 inhibits CYP3A4 and raises felodipine exposure, increasing vasodilatory effects such as hypotension, flushing, headache and peripheral edema. Additive calcium channel blockade also occurs.
How serious is the interaction between Diltiazem and Felodipine?
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 routine combination of two calcium channel blockers; if used, start with a low felodipine dose and monitor blood pressure, heart rate and edema.
What other medicines interact with Felodipine?
MediHelp also lists interactions of Felodipine with, for example, Itraconazole, Aldesleukin, Amifostine. The full list is on the Felodipine page.
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