Anastrozole and Warfarin Interaction
Drug interaction information between Anastrozole and Warfarin.
Anastrozole and Warfarin have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Anastrozole and Warfarin. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Research shows that this medicine does not interfere with how the blood thinner works or how much of it stays in your body.
FDA Label Information
7.3 Warfarin In a study conducted in 16 male volunteers, anastrozole did not alter the exposure (as measured by C max and AUC), and anticoagulant activity (as measured by prothrombin time, activated partial thromboplastin time, and thrombin time) of both R- and S-warfarin.
Warfarin Also Interacts With
- Fluoxetine major
- Tamoxifen major
- Ibuprofen moderate
- Aspirin moderate
- Diclofenac moderate
Frequently Asked Questions
What SPL severity band is on file for Anastrozole + Warfarin?
Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Warfarin has 163 labeled pairs on file vs Anastrozole's 2. In the minor band specifically: Anastrozole has 1; Warfarin has 133 (also Atorvastatin, Amlodipine, Omeprazole, Famotidine).
What mechanism field is on file for Anastrozole and Warfarin?
Research shows that this medicine does not interfere with how the blood thinner works or how much of it stays in your body.
Warfarin carries more major-labeled pairs than Anastrozole
SPL source-record counts only. This page's band is minor · classes on file: Anastrozole (Aromatase Inhibitor); Warfarin (Vitamin K Antagonist (Anticoagulant)).
Warfarin has 2 major-labeled pairs vs Anastrozole's 1. This page itself is in the minor band, not the major band.
1 major · 0 moderate · 1 minor · 2 total
Anastrozole has no other minor-band peer in this dataset besides Warfarin.
2 major · 28 moderate · 133 minor · 163 total
- Other minor peers for Warfarin
- Atorvastatin
- Amlodipine
- Omeprazole
- Famotidine
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.