What the FDA labels say about taking them together
Exemestane and tamoxifen
Exemestane's FDA label of September 12, 2024 names tamoxifen in its warnings and precautions section; the tamoxifen labels PlainMeds reads (2) do not name exemestane. The exemestane label: “Percent Change in BMD from Baseline to 24 months, Exemestane vs. Control 1 IES 027 BMD Exemestane N=29 Tamoxifen 1 N=38 Exemestane N=59 Placebo 1 N=65 Lumbar spine (%) -3.1 -0.2 -3.5 -2.4 Femoral neck (%) -4.2 -0.3 -4.6 …”
Check it at the source: the exemestane FDA label on DailyMed (effective September 12, 2024, Breckenridge Pharmaceutical, Inc.); the tamoxifen FDA label on DailyMed (effective December 18, 2025, Actavis Pharma, Inc.).
What does the exemestane label say about tamoxifen?
Exemestane label, warnings and precautionsPercent Change in BMD from Baseline to 24 months, Exemestane vs. Control 1 IES 027 BMD Exemestane N=29 Tamoxifen 1 N=38 Exemestane N=59 Placebo 1 N=65 Lumbar spine (%) -3.1 -0.2 -3.5 -2.4 Femoral neck (%) -4.2 -0.3 -4.6 -2.6 During adjuvant treatment with exemestane, women with osteoporosis or at risk of osteoporosis should have their bone mineral density formally assessed by bone densitometry at the commencement of treatment.
Source: FDA drug label (Exemestane), Breckenridge Pharmaceutical, Inc., effective September 12, 2024 (SPL set 4e3fd382-19f5-4ded-ab22-39d5b1b2f366), via openFDA; the full label on DailyMed
What does the tamoxifen label say about exemestane?
Tamoxifen's label (effective December 18, 2025) and its 1 other brand-application label do not name exemestane in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Tamoxifen Citrate), Actavis Pharma, Inc., effective December 18, 2025 (SPL set 9b8a4211-120f-4981-ad69-928accb97637), 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
| Exemestane | Tamoxifen | |
|---|---|---|
| Labeled for | Breast cancer | Breast cancer |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.748 per tablet 25 mg tablet | $0.277 per tablet 20 mg tablet |
| 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