Sunday March 29, 2009


Q: Which commonly used drug for GI prophylaxis in Critical Care Units may decrease the efficacy of Plavix (Clopidogrel)?



Answer: Omeprazole (Prilosec)

Out of all PPIs (Proton Pump Inhibitors), Omeprazole is said to have most evidence of decreasing the efficacy of Plavix - which may lead to clinically evident cardiovascular events.

PPIs inhibit the enzyme CYP2C19 - the main enzyme which converts plavix (prodrug) to its active metabolite.



References: click to get abstract

1. Risk of Adverse Outcomes Associated With Concomitant Use of Clopidogrel and Proton Pump Inhibitors Following Acute Coronary Syndrome JAMA. 2009;301(9):937-944.

2. Influence of Omeprazole on the Antiplatelet Action of Clopidogrel Associated With Aspirin - J Am Coll Cardiol, 2008; 51:256-260

3. Initial Assessment of Clinical Impact of a Drug Interaction Between Clopidogrel and Proton Pump Inhibitors - J. Am. Coll. Cardiol., September 16, 2008; 52(12): 1038 - 1039.

4. Omeprazole: A Possible New Candidate Influencing the Antiplatelet Effect of Clopidogrel - J. Am. Coll. Cardiol., January 22, 2008; 51(3): 261 - 263