What the FDA labels say about taking them together
Estradiol and ketoconazole
Estradiol's FDA label of April 3, 2024 names ketoconazole in its drug interactions section; the ketoconazole label PlainMeds reads does not name estradiol. The estradiol label: “Inhibitors of CYP3A4, such as erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir, and grapefruit juice, may increase plasma concentrations of estrogens and result in adverse reactions.”
Check it at the source: the estradiol FDA label on DailyMed (effective April 3, 2024, Amneal Pharmaceuticals LLC); the ketoconazole FDA label on DailyMed (effective January 28, 2026, E. Fougera & Co. a division of Fougera Pharmaceuticals, LLC).
What does the estradiol label say about ketoconazole?
Estradiol label, drug interactionsInhibitors of CYP3A4 such as erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir and grapefruit juice may increase plasma concentrations of estrogens and may result in adverse reactions.
Source: FDA drug label (Divigel, NDA022038), Vertical Pharmaceuticals, LLC, effective February 27, 2026 (SPL set 59e610dc-883e-4f07-9ec6-a5841b0bf9fb), via openFDA
Source: FDA drug label (YUVAFEM), Amneal Pharmaceuticals LLC, effective April 3, 2024 (SPL set 30c7f6ba-7a9e-4853-b3e4-e00a46560224), via openFDA; the full label on DailyMed
What does the ketoconazole label say about estradiol?
Ketoconazole's label (effective January 28, 2026) does not name estradiol in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (ketoconazole), E. Fougera & Co. a division of Fougera Pharmaceuticals, LLC, effective January 28, 2026 (SPL set cad7c647-34a9-4e4e-83b3-8d78e58f588f), 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
| Estradiol | Ketoconazole | |
|---|---|---|
| Labeled for | Menopause symptoms, Breast cancer, Osteoporosis | Fungal infections |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.0635 per tablet 1 mg tablet | $0.249 per gram 2% cream |
| Shortage now | No current entry | 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