Ketoconazole and Alosetron Interaction
Drug interaction information between Ketoconazole and Alosetron.
Ketoconazole and Alosetron have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Ketoconazole and Alosetron. 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
Ketoconazole stops the body from breaking down alosetron as quickly as usual, which increases the amount of drug in your blood.
FDA Label Information
7.2 CYP3A4 Inhibitors Ketoconazole is a known strong inhibitor of CYP3A4. In a pharmacokinetic study, 38 healthy female subjects received ketoconazole 200 mg twice daily for 7 days, with coadministration of alosetron 1 mg on the last day. Ketoconazole increased mean alosetron plasma concentrations (AUC) by 29%.
Ketoconazole Also Interacts With
- Alfuzosin major
- Dronedarone major
- Ranolazine major
- Saxagliptin major
- Sildenafil major
Alosetron Also Interacts With
- Clarithromycin moderate
- Itraconazole moderate
- Voriconazole moderate
- Estradiol minor
- Hydralazine minor
Frequently Asked Questions
What SPL severity band is on file for Ketoconazole + Alosetron?
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?
Ketoconazole has 113 labeled pairs on file vs Alosetron's 12. In the minor band specifically: Ketoconazole has 85 (also Abiraterone, Acetaminophen/Oxycodone, Amphotericin B, Apixaban); Alosetron has 9 (also Estradiol, Hydralazine, Theophylline, Cimetidine).
What mechanism field is on file for Ketoconazole and Alosetron?
Ketoconazole stops the body from breaking down alosetron as quickly as usual, which increases the amount of drug in your blood.
Ketoconazole carries more major-labeled pairs than Alosetron
SPL source-record counts only. This page's band is minor · classes on file: Ketoconazole (Azole Antifungal); Alosetron (5-HT3 Antagonist (IBS-D)).
Ketoconazole has 6 major-labeled pairs vs Alosetron's 0. This page itself is in the minor band, not the major band.
6 major · 22 moderate · 85 minor · 113 total
- Other minor peers for Ketoconazole
- Abiraterone
- Acetaminophen/Oxycodone
- Amphotericin B
- Apixaban
0 major · 3 moderate · 9 minor · 12 total
- Other minor peers for Alosetron
- Estradiol
- Hydralazine
- Theophylline
- Cimetidine
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.