Baxter has decided to halt the production of Heparin, a blood thinner drug that has been reported as causing severe reactions and possibly death. Over 350 reports since the end of last year have been made to the U.S. Food and Drug Administration that cited health issues related to Heparin injections.

Typically, the reports are related to patients in kidney dialysis or heart surgery. Beyond reactions, there are also death-related allegations, but officials caution against making an immediate connection.

“While we have reports of four deaths at this time, it is not possible to establish a relationship between the deaths and the use of heparin. To date, a cause to the adverse events has not been identified,” Jenkins said.

Symptoms of adverse reactions include difficulty breathing, falling blood pressure and nausea. The concern is because these reactions have happened from dosages as low as 1000 units per milliliter to 50,000 units.