The Food and Drug Administration (FDA) has expanded its warnings on Pfizer and Moderna COVID-19 vaccines about the risks of two heart conditions. These manufacturers, the two main COVID-19 vaccine providers,

U.S. health officials have expanded warnings about a rare heart side effect associated with the two leading COVID-19 vaccines.

The Food and Drug Administration said Wednesday it was expanded existing warnings on the two leading COVID vaccines about a rare heart side effect mainly seen in young men, despite previous guidance from the Centers for Disease Control and Prevention that said there was no increased risk.