What the FDA labels say about taking them together
Hydroxychloroquine and tamoxifen
Hydroxychloroquine's FDA label of October 8, 2024 names tamoxifen in its warnings and precautions section; the tamoxifen labels PlainMeds reads (2) do not name hydroxychloroquine. The hydroxychloroquine label: “… than five years, renal impairment, use of concomitant drug products such as tamoxifen citrate, and concurrent macular disease.”
Check it at the source: the hydroxychloroquine FDA label on DailyMed (effective October 8, 2024, ANI Pharmaceuticals, Inc.); the tamoxifen FDA label on DailyMed (effective December 18, 2025, Actavis Pharma, Inc.).
What does the hydroxychloroquine label say about tamoxifen?
Hydroxychloroquine label, warnings and precautionsRisk factors for retinal damage include daily hydroxychloroquine sulfate dosages ≥5 mg/kg of actual body weight, durations of use greater than five years, renal impairment, use of concomitant drug products such as tamoxifen citrate, and concurrent macular disease.
Source: FDA drug label (SOVUNA), ANI Pharmaceuticals, Inc., effective October 8, 2024 (SPL set dd441154-b196-4d4c-bc56-2e37f345ef8d), via openFDA; the full label on DailyMed
What does the tamoxifen label say about hydroxychloroquine?
Tamoxifen's label (effective December 18, 2025) and its 1 other brand-application label do not name hydroxychloroquine 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
| Hydroxychloroquine | Tamoxifen | |
|---|---|---|
| Labeled for | Rheumatoid arthritis | Breast cancer |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.149 per tablet 200 mg tablet | $0.277 per tablet 20 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