Aprepitant and Diltiazem Interaction
Drug interaction information between Aprepitant and Diltiazem.
Aprepitant and Diltiazem have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Aprepitant and Diltiazem. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Diltiazem slows down the body's ability to process aprepitant, which can increase the amount of aprepitant in your blood.
What To Do
Avoid taking these two medications at the same time.
FDA Label Information
Intervention Avoid concomitant use of aprepitant Examples Moderate inhibitor: diltiazem Strong inhibitors: ketoconazole, itraconazole, nefazodone, troleandomycin, clarithromycin, ritonavir, nelfinavir Strong CYP3A4 Inducers Clinical Impact Substantially decreased exposure of aprepitant in patients chronically taking a strong CYP3A4 inducer may decrease the efficacy of aprepitant [see Clinical Pharmacology ( 12.3 )] . Intervention Avoid concomitant use of aprepitant Examples Moderate inhibitor: diltiazem Strong inhibitors: ketoconazole, itraconazole, nefazodone, troleandomycin,...
Aprepitant Also Interacts With
- Pimozide major
- Alprazolam moderate
- Methylprednisolone moderate
- Ketoconazole moderate
- Clarithromycin moderate
Diltiazem Also Interacts With
- Ezetimibe major
- Ezetimibe/Simvastatin major
- Simvastatin major
- Theophylline major
- Rifampin moderate
Frequently Asked Questions
Can I take Aprepitant and Diltiazem together?
This is a moderate interaction. Avoid taking these two medications at the same time.
How serious is the interaction between Aprepitant and Diltiazem?
This interaction is classified as "moderate" severity by the FDA. Moderate interactions may worsen your condition or change how your medications work.
Why do Aprepitant and Diltiazem interact?
Diltiazem slows down the body's ability to process aprepitant, which can increase the amount of aprepitant in your blood.
Understanding the Aprepitant and Diltiazem Interaction
FDA-approved prescribing information for these two drugs flags their combination as a moderate-severity interaction. Aprepitant belongs to the NK1 Receptor Antagonist (Antiemetic) class and Diltiazem belongs to the Calcium Channel Blocker class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Diltiazem slows down the body's ability to process aprepitant, which can increase the amount of aprepitant in your blood. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Aprepitant has 22 total documented interactions on file in this dataset, and Diltiazem has 46. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Avoid taking these two medications at the same time. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Aprepitant or Diltiazem based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.