Clopidogrel bisulfate: ongoing safety review.(Safety and Efficacy Issues)

United States of America -- The Food and Drug Administration (FDA) is aware of published reports that clopidogrel (Ptavix[R]) is less effective in some patients than it is in others. Differences in effectiveness may be due to genetic differences in the way the body metabolizes clopidogrel (1,2) or that using certain other drugs with clopidogrel can interfere with how the body metabolizes clopidogrel (3).

Clopidogrel is an antiplatelet drug that is used to prevent blood clots that could lead to heart attacks or strokes in patients at risk for these problems. The drug clopidogrel is a "pro-drug" which means that it has to be metabolized by the body before it can be biologically …