DALLAS, March 12, 2010 - Today, the U.S. Food and Drug Administration (FDA) issued a drug safety communication to patients and healthcare professionals regarding the use of clopidogrel, an anti-clotting medication.

The FDA is requiring a “Boxed Warning” on the label of clopidogrel to tell patients and healthcare providers that certain patients may lack genetic factors required to effectively metabolize the drug. These “poor metabolizers" may not receive the full benefits of clopidogrel.

According to the FDA, approximately 2 to 14 percent of the population are poor metabolizers of clopidogrel.

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

In addition to alerting patients and providers to metabolic differences, the boxed warning will tell healthcare providers that genetic testing can identify individuals who are poor metabolizers of the drug. It also advises providers to consider other anti-platelet medications or alternative dosing of clopidogrel in patients who are poor metabolizers.

The American Heart Association advises patients on clopidogrel not to stop taking it unless recommended by a physician; share with their physician any concerns; and ask if they should consider genetic testing.

The current warning about poor metabolizers was added to the drug’s package insert in May 2009, so the current FDA communication requires the drug manufacturer to move the information to the outside of the package.

Click here to view the full FDA Drug Safety Communication. 


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