What the FDA labels say about taking them together
Simvastatin and warfarin
Simvastatin's FDA label of March 28, 2025 names warfarin in its drug interactions section; the warfarin label PlainMeds reads does not name simvastatin. The simvastatin label: “… bleeding and/or increased INR in patients taking concomitant statins and warfarin.”
Check it at the source: the simvastatin FDA label on DailyMed (effective March 28, 2025, Organon LLC); the warfarin FDA label on DailyMed (effective May 29, 2026, Amneal Pharmaceuticals LLC).
What does the simvastatin label say about warfarin?
Simvastatin label, drug interactionsCoumarin Anticoagulants Clinical Impact: ZOCOR may potentiate the effect of coumarin anticoagulants and increase the INR. The concomitant use of ZOCOR (20 to 40 mg) and coumarin anticoagulants increased the INR from a baseline of 1.7 to 1.8 in healthy subjects and from 2.6 to 3.4 in patients with hyperlipidemia. … Intervention: In patients taking coumarin anticoagulants, obtain an INR before starting ZOCOR and frequently enough after initiation, dose titration, or discontinuation to ensure that no significant alteration in INR occurs. Once the INR is stable, monitor INR at regularly recommended intervals.
Source: FDA drug label (ZOCOR), Organon LLC, effective March 28, 2025 (SPL set 8f55d5de-5a4f-4a39-8c84-c53976dd6af9), via openFDA; the full label on DailyMed
What does the warfarin label say about simvastatin?
Warfarin's label (effective May 29, 2026) does not name simvastatin 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
| Simvastatin | Warfarin | |
|---|---|---|
| Labeled for | Heart attack and coronary artery disease, High cholesterol, High triglycerides | Blood clots (DVT and PE), Atrial fibrillation |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.0321 per tablet 20 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