Drug interaction between clopidogrel and omeprazole #aha09

The FDA notified healthcare professionals of new safety information concerning a drug interaction between clopidogrel, an anti-clotting medication, and omeprazole, a proton pump inhibitor (PPI) used to reduce stomach acid.

The FDA notes that they have new data showing that when healthy volunteers received clopidogrel with omeprazole, clopidogrel was less effective in its anti-clotting action than when given without omeprazole. The data are not yet peer-reviewed and published; however the FDA recommends that patients who are using clopidogrel should consult with their healthcare provider if they are currently taking or considering taking omeprazole, including Prilosec OTC.

Clopidogrel is often prescribed to people who have chest pain, have had a heart attack or undergone an artery-opening procedure such as angioplasty or stenting. Effective anti-clotting therapy is proven to reduce the risk of another heart event.

Since clopidogrel can cause bleeding in the stomach, medications like omeprazole may be used in combination to reduce stomach acid and prevent stomach bleeding. Omeprazole is available both by prescription and as an over-the-counter preparation (Prilosec OTC) used to treat frequent heartburn.

The FDA public health advisory lists other medications including antacids and medicines that reduce stomach acid (ranitidine, famotidine, nizatidine) that do not interfere with the anti-clotting activity of clopidogrel, but they suggest that cimetidine should not be used.

The FDA’s statement is not based on any new published, peer-reviewed clinical trials showing changes in cardiovascular outcomes.