What the FDA labels say about taking them together
Gefitinib and warfarin
Gefitinib's FDA label of February 28, 2023 names warfarin in its drug interactions section; the warfarin label PlainMeds reads does not name gefitinib. The gefitinib label: “Hemorrhage in patients taking warfarin: Monitor changes in prothrombin time or INR.”
Check it at the source: the gefitinib FDA label on DailyMed (effective February 28, 2023, AstraZeneca Pharmaceuticals LP); the warfarin FDA label on DailyMed (effective May 29, 2026, Amneal Pharmaceuticals LLC).
What does the gefitinib label say about warfarin?
Gefitinib label, drug interactionsHemorrhage in patients taking warfarin: Monitor changes in prothrombin time or INR.
Source: FDA drug label (IRESSA), AstraZeneca Pharmaceuticals LP, effective February 28, 2023 (SPL set 827d60e8-7e07-41b7-c28b-49ef1c4a5a41), via openFDA; the full label on DailyMed
What does the warfarin label say about gefitinib?
Warfarin's label (effective May 29, 2026) does not name gefitinib 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
| Gefitinib | Warfarin | |
|---|---|---|
| Labeled for | Lung cancer | Blood clots (DVT and PE), Atrial fibrillation |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | n/a | $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