RELATED: If You Have This in Your Blood, You’re 42 Percent More Likely to Have a Heart Attack. A 2015 study published in PLOS One highlighted the link between commonly prescribed antacid drugs and heart attacks. Researchers from Houston Methodist and Stanford University examined health documents for nearly 3 million patients across the U.S. to determine whether certain antacid medications raise the risk of heart attack. According to the study, patients using proton pump inhibitors (PPIs) have a 16 to 21 percent increased risk of heart attack compared to individuals who do not use this medication. RELATED: This Is The Single Best Way to Predict Your Heart Attack Risk, Experts Say. This risk is prevalent in the entire general population, not just older adults or people with a history of acute coronary syndrome (ACS) who are more at risk of having a heart attack, the researchers said. This study was one of the first to show a clear risk of PPIs for the general population, as previous research had health officials believing that the risk was relegated to a small subset of patients who had coronary artery disease and were also using the anti-platelet drug clopidogrel to prevent future heart attacks. “Investigators originally assumed this was due to a drug-drug interaction between these compounds, and the FDA went so far as to release a warning about their concomitant use,” study lead author Nicholas Leeper, MD, professor of surgery at the Stanford University Medical Center, explained in a statement. “This led us to use powerful ‘big-data’ approaches to try to determine whether PPIs might in fact be associated with risk in ‘all comers.’” The researchers say PPIs are primarily used for those who have gastroesophageal reflux disease (GERD). However, alternative medications used to treat GERD may not have the same heart attack risk. According to the study, the researchers found that patients who used H2 blockers as an alternative treatment for GERD did not have an increased risk of having a heart attack. Unfortunately, doctors tend to use PPIs as the first line of medication defense in GERD cases.ae0fcc31ae342fd3a1346ebb1f342fcb “Both medications work by blocking and decreasing the production of stomach acid, but PPIs are considered stronger and faster in reducing stomach acids,” the experts at Healthline explained when comparing PPIs and H2 blockers. RELATED: For more health content delivered straight to your inbox, sign up for our daily newsletter. According to the study, PPIs are used widely in the U.S. and across the globe. Around 113 million PPI prescriptions are filled each year worldwide, and in the U.S. alone, around 21 million people had at least one PPI prescription in 2009—making it the third-highest medication sold in the country. But PPIs are not only available through prescriptions: According to Medline Plus, there are many types of PPIs—some of which are available over-the-counter (OTC), like Prilosec, Nexium, Prevacid, and Zegerid. The researchers say that OTC PPI sales combined with prescription sales end up resulting in more than $13 billion sales worldwide for this one class of medication. “Our report raises concerns that these drugs—which are available over the counter and are among the most commonly prescribed drugs in the world—may not be as safe as we previously assumed,” Leeper said. RELATED: If You Take This Medication, You’re More Likely to Get a Blood Clot.