What the FDA labels say about taking them together
Diltiazem and drospirenone/ethinyl estradiol
Drospirenone/ethinyl estradiol's FDA label of May 29, 2025 names diltiazem in its drug interactions section; the diltiazem labels PlainMeds reads (4) do not name drospirenone/ethinyl estradiol. The drospirenone/ethinyl estradiol label: “Concomitant administration of moderate or strong CYP3A4 inhibitors such as azole antifungals, verapamil, macrolides, diltiazem, and grapefruit juice can increase the plasma concentrations of the estrogen or the …”
Check it at the source: the diltiazem FDA label on DailyMed (effective August 7, 2026, Bausch Health US, LLC); the drospirenone/ethinyl estradiol FDA label on DailyMed (effective May 29, 2025, Bayer HealthCare Pharmaceuticals Inc.).
What does the diltiazem label say about drospirenone/ethinyl estradiol?
Diltiazem's label (effective August 7, 2026) and its 3 other brand-application labels do not name drospirenone/ethinyl estradiol 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 drospirenone/ethinyl estradiol label say about diltiazem?
Drospirenone/ethinyl estradiol label, drug interactionsConcomitant administration of moderate or strong CYP3A4 inhibitors such as azole antifungals (e.g., ketoconazole, itraconazole, voriconazole, fluconazole), verapamil, macrolides (e.g., clarithromycin, erythromycin), diltiazem, and grapefruit juice can increase the plasma concentrations of the estrogen or the progestin or both.
Source: FDA drug label (Yaz), Bayer HealthCare Pharmaceuticals Inc., effective May 29, 2025 (SPL set 065f33e4-b587-4e66-b896-ca9ab7b7c876), 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 | Drospirenone/ethinyl estradiol | |
|---|---|---|
| Labeled for | High blood pressure, Angina, Atrial fibrillation | Acne, Birth control |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.144 per capsule 24h ER(cd) 120 mg capsule | $0.151 per tablet 3-0.03 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