Product information about the Moderna and Pfizer-BioNTech vaccines now warns about the increased risk for heart inflammation, a rare side effect of the shots.
US government health officials say, however, that the benefits of the vaccines against Covid-19 outweigh the risk posed by the side effect, which appears most common among people under 30.
The Food and Drug Administration said the risk particularly follows the second dose of the Covid-19 vaccines, and symptoms usually appear within a few days of vaccination. The fact sheets say people should seek immediate medical care if they have chest pain, shortness of breath, or a fast, fluttering or pounding heart after vaccination.
The FDA noted the change in fact sheets for patients and health care providers in a website post dated Friday. The action followed discussion of the issue Wednesday by a committee that advises the Centers for Disease Control and Prevention on vaccinations.
After that meeting, top government health officials and medical organizations issued an unusual joint statement saying that the side effect is “extremely rare” and usually mild in young people, and that many recover on their own or with minimal treatment.