This page explains what happens if Omeprazole and Warfarin are taken together, according to official sources.
No meaningful effect on warfarin anticoagulation; PPI gastroprotection
Omeprazole does not meaningfully alter warfarin's anticoagulant effect, as it does not affect active S-warfarin or coagulation test results. Proton pump inhibitors (PPIs) are commonly used to protect the stomach and reduce the risk of serious upper gastrointestinal bleeding in patients on warfarin.
Continue standard routine INR monitoring for warfarin therapy. No dose adjustment is routinely required for omeprazole, and PPI co-therapy provides protective gastric acid suppression.
Last updated: Sep 25, 2026
Before changing or stopping any medicine, ask your doctor or pharmacist. Never stop your medicine on your own.