The U.S. Food and Drug Administration on Wednesday urged doctors to limit the use of Bayer AG’s Trasylol heart-surgery drug while the agency reviews research showing the medication heightened risks of heart attack, stroke and kidney problems.

The drug is used to prevent blood loss in patients who undergo artery bypass graft surgery, said the FDA, which issued the advisory to doctors and patients.

“We’re working to evaluate the potential risks and determine whether there is a need for further action,” Dr. Steven Galson, Director of FDA’s Center for Drug Evaluation and Research, said in a statement. “In the meantime, we advise providers to carefully assess the benefits and risks of the drug for their patients.”

The FDA urged physicians to consider limiting the use of Trasylol to only those situations where the benefit of reducing blood loss during surgery outweighed the risks.

The FDA said it plans to hold an advisory committee meeting later this year to discuss existing data on the benefits and risks of the drug as well as to determine if more safety measures are needed.

Researchers reported last month in the New England Journal of Medicine that Trasylol doubled the risk of kidney failure and stroke and increased the chance of heart failure or heart attack by 55 percent.

German-based Bayer last month said the results were “not consistent with the more than 15 years of clinical data and experience Bayer has amassed on this drug.”

A company spokesman in Germany said Bayer will cooperate with the FDA and other regulators. “We’re analyzing the data we have on the drug,” he said.

Bayer also said that it will send out an information letter in the next few days to heart surgeons, anesthetists and hospital pharmacists about Trasylol.

Shares of Bayer were down 31 cents to $40.01 in mid-afternoon trading on the New York Stock Exchange.