Lansoprazole and Ketoconazole Interaction
Drug interaction information between Lansoprazole and Ketoconazole.
Lansoprazole and Ketoconazole have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Lansoprazole and Ketoconazole. 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 needs stomach acid to dissolve and enter your body, but lansoprazole reduces the amount of acid your stomach makes.
FDA Label Information
Drugs Dependent on Gastric pH for Absorption (e.g., iron salts, erlotinib, dasatinib, nilotinib, mycophenolate mofetil, ketoconazole/itraconazole) Clinical Impact: Lansoprazole can reduce the absorption of other drugs due to its effect on reducing intragastric acidity.
Lansoprazole Also Interacts With
- Amoxicillin major
- Clarithromycin major
- Rifampin moderate
- Tacrolimus Topical moderate
- Warfarin minor
Ketoconazole Also Interacts With
- Alfuzosin major
- Dronedarone major
- Ranolazine major
- Saxagliptin major
- Sildenafil major
Frequently Asked Questions
What SPL severity band is on file for Lansoprazole + Ketoconazole?
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 Lansoprazole's 14. In the minor band specifically: Lansoprazole has 10 (also Warfarin, Methotrexate, Itraconazole, Voriconazole); Ketoconazole has 85 (also Abiraterone, Acetaminophen/Oxycodone, Alosetron, Amphotericin B).
What mechanism field is on file for Lansoprazole and Ketoconazole?
Ketoconazole needs stomach acid to dissolve and enter your body, but lansoprazole reduces the amount of acid your stomach makes.
Ketoconazole carries more major-labeled pairs than Lansoprazole
SPL source-record counts only. This page's band is minor · classes on file: Lansoprazole (Proton Pump Inhibitor (PPI)); Ketoconazole (Azole Antifungal).
Ketoconazole has 6 major-labeled pairs vs Lansoprazole's 2. This page itself is in the minor band, not the major band.
2 major · 2 moderate · 10 minor · 14 total
- Other minor peers for Lansoprazole
- Warfarin
- Methotrexate
- Itraconazole
- Voriconazole
6 major · 22 moderate · 85 minor · 113 total
- Other minor peers for Ketoconazole
- Abiraterone
- Acetaminophen/Oxycodone
- Alosetron
- Amphotericin B
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.