Dutasteride and Warfarin Interaction

Drug interaction information between Dutasteride and Warfarin.

Dutasteride and Warfarin have a documented moderate interaction in FDA labeling.

FDA drug labeling documents a moderate-severity interaction between Dutasteride 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.

Drug A

Dutasteride

5-Alpha Reductase Inhibitor

Drug B

Warfarin

Vitamin K Antagonist (Anticoagulant)

How They Interact

There is not enough research to know exactly how these drugs interact, but they might change how your blood-thinning medicine works.

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 (...

Warfarin Also Interacts With

View all Warfarin interactions →

Frequently Asked Questions

What SPL severity band is on file for Dutasteride + 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's 16. In the moderate band specifically: Dutasteride has 2 (also Tamsulosin); Warfarin has 28 (also Ibuprofen, Aspirin, Diclofenac, Desvenlafaxine).

What mechanism field is on file for Dutasteride and Warfarin?

There is not enough research to know exactly how these drugs interact, but they might change how your blood-thinning medicine works.

Warfarin carries more major-labeled pairs than Dutasteride

SPL source-record counts only. This page's band is moderate · classes on file: Dutasteride (5-Alpha Reductase Inhibitor); Warfarin (Vitamin K Antagonist (Anticoagulant)).

Warfarin has 2 major-labeled pairs vs Dutasteride's 1. This page itself is in the moderate band, not the major band.

Dutasteride

1 major · 2 moderate · 13 minor · 16 total

Warfarin

2 major · 28 moderate · 133 minor · 163 total

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.