What the FDA labels say about taking them together
Colesevelam and warfarin
Colesevelam's FDA label of December 28, 2023 names warfarin in its drug interactions section; the warfarin label PlainMeds reads does not name colesevelam. The colesevelam label: “Patients with a susceptibility to deficiencies of vitamin K or other fat-soluble vitamins may be at increased risk.”
Check it at the source: the colesevelam FDA label on DailyMed (effective December 28, 2023, A-S Medication Solutions); the warfarin FDA label on DailyMed (effective May 29, 2026, Amneal Pharmaceuticals LLC).
What does the colesevelam label say about warfarin?
Colesevelam label, drug interactionsFor patients on warfarin, monitor International Normalized Ratio (INR) frequently during initiation then periodically ( 7.1 ).
Colesevelam label, warnings and precautionsPatients with a susceptibility to deficiencies of vitamin K (e.g., patients on warfarin, patients with malabsorption syndromes) or other fat-soluble vitamins may be at increased risk.
Source: FDA drug label (COLESEVELAM HYDROCHLORIDE), NDA021176 (Cosette), as published by A-S Medication Solutions, effective December 28, 2023 (SPL set 0127afae-8d8d-43f2-97f9-4f99f6947e81), via openFDA; the full label on DailyMed
What does the warfarin label say about colesevelam?
Warfarin's label (effective May 29, 2026) does not name colesevelam in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Warfarin Sodium), Amneal Pharmaceuticals LLC, effective May 29, 2026 (SPL set 558b7a0d-5490-4c1b-802e-3ab3f1efe760), 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
| Colesevelam | Warfarin | |
|---|---|---|
| Labeled for | High cholesterol, Type 2 diabetes | Blood clots (DVT and PE), Atrial fibrillation |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.262 per tablet 625 mg tablet | $0.093 per tablet 2 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