People taking the clot-preventing drug Plavix and an acid-reducing proton pump inhibitor medication after a heart attack have a dramatically higher risk of a second heart attack than those taking Plavix alone, a Canadian study finds.

 

This increased risk could have enormous public health implications. Proton pump inhibitors such as Prilosec and Prevacid are among the most widely prescribed drugs, and Plavix (clopidogrel) is the second highest-selling drug in the world, the researchers said.

 

The Canadian study of 13,636 people hospitalized with heart attacks between 2002 and 2007 was started as a response to basic science studies showing that the acid-lowering drugs turned off Plavix, said Dr. David N. Juurlink, head of the division of clinical pharmacology and toxicology at Sunnybrook Health Sciences Centre in Toronto.

 

"We linked prescribing data with hospital data on these more than 13,000 patients prescribed Plavix after a heart attack and found that people on certain proton pump inhibitors had a 40 percent increased risk of a recurrence," said Juurlink, lead author of the report, published online Jan. 28 in the Canadian Medical Association Journal.

Plavix had global sales of $7.3 billion in 2007. The drug is marketed by Bristol-Myers Squibb Co. and Sanofi-Aventis SA and has been prescribed to more than 90 million patients around the world.

 

While acid problems itself aren't life threatening, patients on heart attack medication should consult with their physician and explore different options which are safer.

 
The researchers, from the Institute for Clinical Evaluative Sciences (ICES) in Toronto, say that they did not find an increased heart attack risk among patients taking the PPI pantoprazole (Pantoloc). They also did not find an increased risk among patients taking anti-acid medications known as H2 receptor antagonists, such as Pepcid or Zantac.