Dutasteride/Tamsulosin and Warfarin Interaction
Drug interaction information between Dutasteride/Tamsulosin and Warfarin.
Dutasteride/Tamsulosin and Warfarin have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Dutasteride/Tamsulosin 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
One part of this combination medicine has not been fully tested with blood thinners, so it is unclear how they might affect each other.
FDA Label Information
7.2 Warfarin Dutasteride Concomitant administration of dutasteride 0.5 mg/day for 3 weeks with warfarin does not alter the steady-state pharmacokinetics of the S- or R-warfarin isomers or alter the effect of warfarin on prothrombin time [see Clinical Pharmacology ( 12.3 ) ] . Tamsulosin A definitive drug-drug interaction trial between tamsulosin hydrochloride and warfarin was not conducted. Caution should be exercised with concomitant administration of warfarin and tamsulosin-containing products, including dutasteride and tamsulosin hydrochloride capsules [see Warnings and Precautions (...
Dutasteride/Tamsulosin Also Interacts With
- Furosemide major
- Tamsulosin moderate
- Paroxetine minor
- Atenolol minor
- Diltiazem minor
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 Dutasteride/Tamsulosin + Warfarin?
Compiled FDA labeling labels this pair moderate. 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 Dutasteride/Tamsulosin's 15. In the moderate band specifically: Dutasteride/Tamsulosin has 2 (also Tamsulosin); Warfarin has 28 (also Ibuprofen, Aspirin, Diclofenac, Desvenlafaxine).
What mechanism field is on file for Dutasteride/Tamsulosin and Warfarin?
One part of this combination medicine has not been fully tested with blood thinners, so it is unclear how they might affect each other.
Warfarin carries more major-labeled pairs than Dutasteride/Tamsulosin
SPL source-record counts only. This page's band is moderate · classes on file: Dutasteride/Tamsulosin (5-ARI / Alpha-Blocker Combination); Warfarin (Vitamin K Antagonist (Anticoagulant)).
Warfarin has 2 major-labeled pairs vs Dutasteride/Tamsulosin's 1. This page itself is in the moderate band, not the major band.
1 major · 2 moderate · 12 minor · 15 total
- Other moderate peers for Dutasteride/Tamsulosin
- Tamsulosin
2 major · 28 moderate · 133 minor · 163 total
- Other moderate peers for Warfarin
- Ibuprofen
- Aspirin
- Diclofenac
- Desvenlafaxine
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.