Dutasteride and Tamsulosin Interaction

Drug interaction information between Dutasteride and Tamsulosin.

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

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

Tamsulosin

Alpha-1 Adrenergic Blocker

How They Interact

These drugs are processed by the same system in your liver, which could change the amount of medicine that stays in your blood.

FDA Label Information

7 DRUG INTERACTIONS There have been no drug interaction trials using dutasteride and tamsulosin hydrochloride capsules. Because of the potential for drug-drug interactions, use caution when prescribing a dutasteride-containing product, including dutasteride and tamsulosin hydrochloride capsules, to patients taking potent, chronic CYP3A4 enzyme inhibitors (e.g., ritonavir) [see Clinical Pharmacology ( 12.3 ) ] . Tamsulosin Strong and Moderate Inhibitors of CYP3A4 or CYP2D6: Tamsulosin is extensively metabolized, mainly by CYP3A4 or CYP2D6.

Tamsulosin Also Interacts With

View all Tamsulosin interactions →

Frequently Asked Questions

What SPL severity band is on file for Dutasteride + Tamsulosin?

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?

Tamsulosin has 18 labeled pairs on file vs Dutasteride's 16. In the moderate band specifically: Dutasteride has 2 (also Warfarin); Tamsulosin has 8 (also Paroxetine, Warfarin, Erythromycin, Terbinafine).

What mechanism field is on file for Dutasteride and Tamsulosin?

These drugs are processed by the same system in your liver, which could change the amount of medicine that stays in your blood.

Tamsulosin's labeled portfolio outnumbers Dutasteride

SPL source-record counts only. This page's band is moderate · classes on file: Dutasteride (5-Alpha Reductase Inhibitor); Tamsulosin (Alpha-1 Adrenergic Blocker).

Dutasteride

1 major · 2 moderate · 13 minor · 16 total

  • Other moderate peers for Dutasteride
  • Warfarin
Tamsulosin

1 major · 8 moderate · 9 minor · 18 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.