Terazosin and Allopurinol Interaction
Drug interaction information between Terazosin and Allopurinol.
Terazosin and Allopurinol have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Terazosin and Allopurinol. 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
These medications have been used together in clinical trials without any reported problems. There is no known negative interaction between them.
FDA Label Information
Terazosin has been used concomitantly in at least 50 patients on the following drugs or drug classes: analgesic/anti-inflammatory (e.g., acetaminophen, aspirin, codeine, ibuprofen, indomethacin); antibiotics (e.g., erythromycin, trimethoprim and sulfamethoxazole); anticholinergic/sympathomimetics (e.g., phenylephrine hydrochloride, phenylpropanolamine hydrochloride, pseudoephedrine hydrochloride); antigout (e.g., allopurinol); antihistamines (e.g., chlorpheniramine); cardiovascular agents (e.g., atenolol, hydrochlorothiazide, methyclothiazide, propranolol); corticosteroids;...
Terazosin Also Interacts With
- Hydrochlorothiazide minor
- Ibuprofen minor
- Aspirin minor
- Atenolol minor
- Acetaminophen minor
Allopurinol Also Interacts With
- Pegloticase major
- Cyclosporine moderate
- Amoxicillin moderate
- Amoxicillin/Clavulanate moderate
- Warfarin minor
Frequently Asked Questions
What SPL severity band is on file for Terazosin + Allopurinol?
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?
Terazosin has 15 labeled pairs on file vs Allopurinol's 10. In the minor band specifically: Terazosin has 15 (also Hydrochlorothiazide, Ibuprofen, Aspirin, Atenolol); Allopurinol has 6 (also Warfarin, Theophylline, Ampicillin/Sulbactam, Famciclovir).
What mechanism field is on file for Terazosin and Allopurinol?
These medications have been used together in clinical trials without any reported problems. There is no known negative interaction between them.
Allopurinol carries more major-labeled pairs than Terazosin
SPL source-record counts only. This page's band is minor · classes on file: Terazosin (Alpha-1 Blocker); Allopurinol (Xanthine Oxidase Inhibitor).
Allopurinol has 1 major-labeled pair vs Terazosin's 0. This page itself is in the minor band, not the major band.
0 major · 0 moderate · 15 minor · 15 total
- Other minor peers for Terazosin
- Hydrochlorothiazide
- Ibuprofen
- Aspirin
- Atenolol
1 major · 3 moderate · 6 minor · 10 total
- Other minor peers for Allopurinol
- Warfarin
- Theophylline
- Ampicillin/Sulbactam
- Famciclovir
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.