Doxazosin and Tadalafil Interaction
Drug interaction information between Doxazosin and Tadalafil.
Doxazosin and Tadalafil have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Doxazosin and Tadalafil. 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
Both of these medications can lower your blood pressure, and taking them together might cause your blood pressure to drop too low.
FDA Label Information
Clinical pharmacology studies have been conducted with coadministration of tadalafil with doxazosin, tamsulosin or alfuzosin.
Tadalafil Also Interacts With
- Hydralazine/Isosorbide Dinitrate major
- Clarithromycin moderate
- Nirmatrelvir/Ritonavir moderate
- Amlodipine minor
- Metoprolol minor
Frequently Asked Questions
What SPL severity band is on file for Doxazosin + Tadalafil?
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?
Tadalafil has 25 labeled pairs on file vs Doxazosin's 2. In the minor band specifically: Doxazosin has 2 (also Propranolol); Tadalafil has 22 (also Amlodipine, Metoprolol, Tamsulosin, Aspirin).
What mechanism field is on file for Doxazosin and Tadalafil?
Both of these medications can lower your blood pressure, and taking them together might cause your blood pressure to drop too low.
Tadalafil carries more major-labeled pairs than Doxazosin
SPL source-record counts only. This page's band is minor · classes on file: Doxazosin (Alpha-1 Adrenergic Blocker); Tadalafil (PDE5 Inhibitor).
Tadalafil has 1 major-labeled pair vs Doxazosin's 0. This page itself is in the minor band, not the major band.
1 major · 2 moderate · 22 minor · 25 total
- Other minor peers for Tadalafil
- Amlodipine
- Metoprolol
- Tamsulosin
- Aspirin
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.