The drugs, known as proton pump inhibitors (PPIs), raise the risk by between 16 and 21 per cent. They are the third most common drugs in the US, and achieve $13 bn of annual global sales.
It's already known that the drugs damage the lining of the blood vessels, and so researchers from Stanford University surmised that they could also be causing a heart attack.
Their fears were confirmed when they investigated the health records of 2.9 million Americans; they also found that another type of antacid, the H2 blocker, didn't carry the same risk. The popular H2s include Zantac and Tagamet.
Around one in 14 Americans takes a PPI drug.
(Source: PLOS One, 2015; 10 (6): e0124653)