Omeprazole significantly reduces the effectiveness of clopidogrel (Plavix), a blood thinner used to prevent heart attacks and strokes. This interaction can leave patients at higher risk for cardiovascular events, including stent thrombosis in patients with coronary stents.
How This Interaction Works (Mechanism)
Clopidogrel is a prodrug that requires activation by the liver enzyme CYP2C19. Omeprazole is a potent inhibitor of CYP2C19, which blocks the conversion of clopidogrel to its active metabolite. This can reduce clopidogrel's antiplatelet activity by 40 to 50 percent, significantly diminishing its ability to prevent blood clots. The effect is most pronounced with omeprazole and esomeprazole compared to other PPIs.
Source: FDA Drug Safety Communication, 2009 (reaffirmed 2024)
Avoid omeprazole and esomeprazole while taking clopidogrel. If a proton pump inhibitor is needed, pantoprazole is the preferred alternative because it has minimal CYP2C19 inhibition. Alternatively, consider using an H2 blocker like famotidine for acid reduction. The FDA has issued a specific warning about this interaction. Discuss alternatives with your cardiologist and gastroenterologist.
Check More Drug Interactions
Use our free interaction checker to search thousands of drug, supplement, and food combinations.
Open Interaction CheckerFrequently Asked Questions
Omeprazole and Clopidogrel have a severe interaction and should generally not be taken together without close medical supervision. The combination can cause serious, potentially life-threatening side effects. Contact your doctor immediately if you are currently taking both medications.
Omeprazole significantly reduces the effectiveness of clopidogrel (Plavix), a blood thinner used to prevent heart attacks and strokes. This interaction can leave patients at higher risk for cardiovascular events, including stent thrombosis in patients with coronary stents.
Yes. Anytime you are taking multiple medications, supplements, or substances, you should inform your doctor and pharmacist. They can evaluate your specific risk factors (age, kidney function, other medications, medical conditions) and determine whether the Omeprazole and Clopidogrel combination is safe for you, or whether adjustments are needed.
Related Resources
- Supplement interactions with Omeprazole on Health Britannica
- Supplement interactions with Clopidogrel on Health Britannica
- Omeprazole prices and pharmacy comparison on RxGrab
- Clopidogrel prices and pharmacy comparison on RxGrab
- Full drug interaction checker tool
Get Drug Safety Alerts
Subscribe to receive updates on FDA warnings, new drug interactions, and patient safety information.