Popular heartburn drugs, Prilosec, Nexium, Prevacid, and Protonix have been found to significantly increase the risk of a patient having a stroke, according to a new study reported at November’s American Heart Association Meeting. All of these drugs belong to the class of drugs called proton pump inhibitors, or PPIs, and are used to treat heartburn, acid reflux, ulcers, and gastroesophageal reflux disease. Heartburn medications belonging to the H2 blocker class were not found to contribute to stroke.

PPIs: Previously Known Risks

Proton pump inhibitors are popular as both prescription and over the counter drugs used to treat conditions related to excess acid in the stomach or acid coming up the esophagus from the stomach. PPIs work to treat these conditions by reducing the amount of gastric acid in the stomach. They do this by inhibiting part of a complex of enzymes that produce and pump acid in to the stomach.

For most people PPIs are well tolerated, but there are known side effects including some that can be very serious. These include the development of low magnesium levels, which can in turn cause spasms, an irregular heartbeat, and convulsions. PPIs may also cause bone weakness and fractures, a serous type of bacterial infection, and even heart attacks. The U.S. Food and Drug Administration (FDA) has reported on and warned about these risks associated with PPIs

PPIs and Stroke: New Research

Because PPIs were previously found to increase the risk of someone having a heart attack, researchers from Denmark decided to find out if they also increase the risk of ischemic stroke, a stroke caused by a blockage of a blood vessel in the brain. The study investigated the records of nearly 250,000 patients with a medical history of stomach problems. Over the course of six years, 9,489 patients experienced their first ever ischemic stroke.

The researchers were able to determine that the use of a PPI increased the stroke risk in these patients by 21 percent. The lowest amount of increased risk, or no increased risk at all, came with using the lowest doses of these medications. The researchers accounted for the age, gender and medical factors for each patient that could have contributed to the stroke risk.

When the researchers looked at each of the four PPIs individually—Prevacid, Protonix, Nexium, and Prilosec—they found that Protonix, at the highest does, increased the risk of stroke by 94 percent. The next greatest increase in stroke risk was seen with the highest doses of Prevacid, at 30 percent.

The new information about PPIs and the risk for stroke is important, especially for patients who are already at an increased risk for having an ischemic incident. The findings correspond to earlier findings that these drugs increase the risk of heart attacks. Patients who take PPIs tend to be older and they are taking the drugs for longer periods of time than previously. The risks and the predominant population using PPIs are troubling. Doctors need to understand this elevated risk and use caution when prescribing PPIs or recommending the use of over the counter PPIs.