Known as proton pump inhibitors (PPIs), these drugs increased people’s overall stroke risk by 21 percent, said study lead author Dr. Thomas Sehested.
However, the risk appears to be driven by people who take high doses, added Sehested, research director at the Danish Heart Foundation in Copenhagen.
“People treated with a low dose of PPIs did not have a high risk of stroke,” he said. “Those treated with the highest doses of PPIs had the highest risk of stroke.”
The extent of risk also depends on the specific PPI taken.
At the highest dose, stroke risk ranged from 30 percent for lansoprazole (Prevacid) to 94 percent for pantoprazole (Protonix), the researchers said.
Takeda Pharmaceutical, the maker of prescription-only Protonix, did not respond to a request for comment.
PPIs specifically affected risk of the most common type of stroke, ischemic stroke, which occurs when a clot blocks blood flow to the brain.
Proton pump inhibitors treat heartburn by blocking acid-producing cells in the lining of the stomach.