What the FDA labels say about taking them together
Calcium acetate and ciprofloxacin
Calcium acetate's FDA label of July 1, 2025 names ciprofloxacin in its drug interactions section; the ciprofloxacin labels PlainMeds reads (3) do not name calcium acetate. The calcium acetate label: “In a study of 15 healthy subjects, a co-administered single dose of 4 calcium acetate tablets approximately 2.7 g, decreased the bioavailability of ciprofloxacin by approximately 50%.”
Check it at the source: the calcium acetate FDA label on DailyMed (effective July 1, 2025, Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc.); the ciprofloxacin FDA label on DailyMed (effective March 2, 2026, Bayer HealthCare Pharmaceuticals Inc.).
What does the calcium acetate label say about ciprofloxacin?
Calcium acetate label, drug interactionsIn a study of 15 healthy subjects, a co-administered single dose of 4 calcium acetate tablets approximately 2.7 g, decreased the bioavailability of ciprofloxacin by approximately 50%.
Source: FDA drug label (calcium acetate), Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc., effective July 1, 2025 (SPL set d48c66a9-26fe-4e1a-a68a-88afe83fb51d), via openFDA; the full label on DailyMed
What does the ciprofloxacin label say about calcium acetate?
Ciprofloxacin's label (effective March 2, 2026) and its 2 other brand-application labels do not name calcium acetate in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Cipro), Bayer HealthCare Pharmaceuticals Inc., effective March 2, 2026 (SPL set 888dc7f9-ad9c-4c00-8d50-8ddfd9bd27c0), 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
| Calcium acetate | Ciprofloxacin | |
|---|---|---|
| Labeled for | n/a | Diarrhea, Urinary tract infections, Bacterial infections |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.170 per capsule 667 mg capsule | $0.123 per tablet 500 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