What the FDA labels say about taking them together
Aprepitant and diltiazem
Aprepitant's FDA label of July 5, 2024 names diltiazem in its drug interactions section; the diltiazem labels PlainMeds reads (4) do not name aprepitant. The aprepitant label: “Use of EMEND with strong or moderate CYP3A4 inhibitors may increase plasma concentrations of aprepitant and result in an increased risk of adverse reactions related to EMEND.”
Check it at the source: the aprepitant FDA label on DailyMed (effective July 5, 2024, Merck Sharp & Dohme LLC); the diltiazem FDA label on DailyMed (effective August 7, 2026, Bausch Health US, LLC).
What does the aprepitant label say about diltiazem?
Aprepitant label, drug interactionsExamples; Moderate inhibitor: diltiazem Strong inhibitors: ketoconazole, itraconazole, nefazodone, troleandomycin, clarithromycin, ritonavir, nelfinavir
Aprepitant label, warnings and precautionsUse of EMEND with strong or moderate CYP3A4 inhibitors (e.g., ketoconazole, diltiazem) may increase plasma concentrations of aprepitant and result in an increased risk of adverse reactions related to EMEND.
Source: FDA drug label (Cinvanti, NDA209296), Heron Therapeutics, Inc., effective April 1, 2026 (SPL set 4c218d3a-a508-4abc-9ed8-a6e8e191d1b4), via openFDA
Source: FDA drug label (EMEND), NDA021549 (Msd), as published by Merck Sharp & Dohme LLC, effective July 5, 2024 (SPL set 696f9e80-9cae-403b-de9e-078343ce4713), via openFDA; the full label on DailyMed
What does the diltiazem label say about aprepitant?
Diltiazem's label (effective August 7, 2026) and its 3 other brand-application labels do not name aprepitant in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (TIAZAC EXTENDED RELEASE), Bausch Health US, LLC, effective August 7, 2026 (SPL set c567fe7e-887e-4291-a0d1-2dd3f25cbf25), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Aprepitant | Diltiazem | |
|---|---|---|
| Labeled for | Nausea and vomiting | High blood pressure, Angina, Atrial fibrillation |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $46.42 per capsule 40 mg capsule | $0.144 per capsule 24h ER(cd) 120 mg capsule |
| Shortage now | A presentation being discontinued | A presentation being discontinued |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once