What the FDA labels say about taking them together
Diltiazem and sirolimus
Sirolimus's FDA label of January 28, 2026 names diltiazem in its drug interactions section; the diltiazem labels PlainMeds reads (4) do not name sirolimus. The sirolimus label: “Drugs that could increase sirolimus blood concentrations: Bromocriptine, cimetidine, cisapride, clotrimazole, danazol, diltiazem, fluconazole, letermovir, protease inhibitors, metoclopramide, nicardipine …”
Check it at the source: the diltiazem FDA label on DailyMed (effective August 7, 2026, Bausch Health US, LLC); the sirolimus FDA label on DailyMed (effective January 28, 2026, Glenmark Pharmaceuticals Inc., USA).
What does the diltiazem label say about sirolimus?
Diltiazem's label (effective August 7, 2026) and its 3 other brand-application labels do not name sirolimus 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
What does the sirolimus label say about diltiazem?
Sirolimus label, drug interactionsDrugs that could increase sirolimus blood concentrations: Bromocriptine, cimetidine, cisapride, clotrimazole, danazol, diltiazem, fluconazole, letermovir, protease inhibitors (e.g., HIV and hepatitis C that include drugs such as ritonavir, indinavir, boceprevir, and telaprevir), metoclopramide, nicardipine, troleandomycin, verapamil
Source: FDA drug label (sirolimus), Glenmark Pharmaceuticals Inc., USA, effective January 28, 2026 (SPL set 57fb4d90-3ccb-4a69-af1e-53be83f7a504), 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
| Diltiazem | Sirolimus | |
|---|---|---|
| Labeled for | High blood pressure, Angina, Atrial fibrillation | Organ transplant rejection |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.144 per capsule 24h ER(cd) 120 mg capsule | $0.723 per tablet 1 mg tablet |
| Shortage now | A presentation being discontinued | No current entry |
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