Olanzapine and Omeprazole Interaction
Drug interaction information between Olanzapine and Omeprazole.
Olanzapine and Omeprazole have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Olanzapine and Omeprazole. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Omeprazole makes the body get rid of olanzapine faster than normal. This could make the olanzapine less effective because there is not enough of it in your system.
What To Do
Your doctor might need to adjust your olanzapine dose to make sure it still works for you.
FDA Label Information
Inducers of CYP1A2 or Glucuronyl Transferase — Omeprazole and rifampin may cause an increase in olanzapine clearance.
Olanzapine Also Interacts With
- Fluoxetine major
- Tetrabenazine moderate
- Warfarin minor
- Diazepam minor
- Carbamazepine minor
Omeprazole Also Interacts With
- Theophylline major
- Clarithromycin moderate
- Clopidogrel moderate
- Darunavir moderate
- Tacrolimus Topical moderate
Frequently Asked Questions
Can I take Olanzapine and Omeprazole together?
This is a minor interaction. Your doctor might need to adjust your olanzapine dose to make sure it still works for you.
How serious is the interaction between Olanzapine and Omeprazole?
This interaction is classified as "minor" severity by the FDA. Minor interactions are unlikely to cause significant problems but should still be mentioned to your healthcare provider.
Why do Olanzapine and Omeprazole interact?
Omeprazole makes the body get rid of olanzapine faster than normal. This could make the olanzapine less effective because there is not enough of it in your system.
Understanding the Olanzapine and Omeprazole Interaction
FDA-approved prescribing information for these two drugs flags their combination as a minor-severity interaction. Olanzapine belongs to the Atypical Antipsychotic class and Omeprazole belongs to the Proton Pump Inhibitor (PPI) class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Omeprazole makes the body get rid of olanzapine faster than normal. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Olanzapine has 26 total documented interactions on file in this dataset, and Omeprazole has 27. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Your doctor might need to adjust your olanzapine dose to make sure it still works for you. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Olanzapine or Omeprazole based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.