The following is taken from WikiDoc News:

Clopidogrel, when taken with PPIs after MI, dramatically increases a patient’s chances of having a second MI, according to a study in the Canadian Medical Association Journal.

Clopidogrel (Plavix) and PPIs like Prilosec and Prevacid are among the most widely prescribed drugs in the world, so these findings could have an enormous public health impact. The Canadian study looked at 13,636 people who had heart attacks between 2002 and 2007. They found those who took clopidogrel along with a PPI had a 40 percent increased chance of having a second MI. Scientists believe the heartburn meds interfere with body’s ability to metabolize the clot-preventing drug. –Brian Blank

Earlier this week CardioBrief reported that the FDA was conducting a safety review of clopidogrel, in part due to inhibition of its effects when administered with other drugs such as PPIs. Here is our earlier post.