What the FDA labels say about taking them together
Cimetidine and hydroxychloroquine
Hydroxychloroquine's FDA label of October 8, 2024 names cimetidine in its drug interactions section; the cimetidine label PlainMeds reads does not name hydroxychloroquine. The hydroxychloroquine label: “Concomitant use of cimetidine resulted in a 2-fold increase of exposure of chloroquine, which is structurally related to hydroxychloroquine.”
Check it at the source: the cimetidine FDA label on DailyMed (effective July 15, 2026, Mylan Pharmaceuticals Inc.); the hydroxychloroquine FDA label on DailyMed (effective October 8, 2024, ANI Pharmaceuticals, Inc.).
What does the cimetidine label say about hydroxychloroquine?
Cimetidine's label (effective July 15, 2026) does 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 (Cimetidine), Mylan Pharmaceuticals Inc., effective July 15, 2026 (SPL set 06c0a509-026f-44e0-9975-a94a8de51d43), via openFDA; the full label on DailyMed
What does the hydroxychloroquine label say about cimetidine?
Hydroxychloroquine label, drug interactionsConcomitant use of cimetidine resulted in a 2-fold increase of exposure of chloroquine, which is structurally related to hydroxychloroquine.
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
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
| Cimetidine | Hydroxychloroquine | |
|---|---|---|
| Labeled for | Acid reflux and ulcers | Rheumatoid arthritis |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.236 per tablet 300 mg tablet | $0.149 per tablet 200 mg tablet |
| Shortage now | No current entry | A presentation being discontinued |
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