Mixing supplements and drugs can be fatal

CHICAGO, Nov. 15 (UPI) -- Many heart patients may be putting their lives in danger by taking supplements with the blood thinning drug Warfarin, U.S. researchers suggest.

Researchers and pharmacists at the Intermountain Medical Center Heart Institute and dietitians from Utah State University in Salt Lake City conducted interviews with 100 atrial fibrillation patients to determine their understanding of potential interactions between supplements and medications, such as Warfarin, also known as Coumadin.

The drug Warfarin is prescribed to prevent blood clots from forming, for those with an irregular heartbeat, people with prosthetic heart valves and people who have suffered a heart attack.

Of the 35 patients combining Warfarin with supplements, 54 percent were unaware of potential interactions. The researchers said that of the 100 most-used supplements, 69 percent interfere with the effectiveness of Warfarin.

"This is an alarming finding," study author Dr. T. Jared Bunch of the Intermountain Medical Center Heart Institute, said in a statement.

Warfarin supplements "compete" in the liver and that changes the way the blood thinner works -- intensifying its active ingredients and increasing the risk of bleeding or reducing its effectiveness and increasing the risk of stroke, Bunch said.

"We have also learned that -- for whatever reason -- patients don't want to tell their doctors that they are taking herbal and dietary supplements," Bunch said. "Physicians must be active in asking about supplement use and not place responsibility on patients."

The findings were presented at the American Health Association's annual scientific session in Chicago.