FDA added heart inflammation warning to Pfizer and Moderna vaccines

The Food and Drug Administration has added a warning to the Pfizer and Moderna vaccine fact sheets that describes a rare but serious heart inflammation problem that's now been attributed to the pharmaceutical companies' COVID-19 vaccines.

The patient and provider fact sheets were revised Friday to include an increased risk of myocarditis, inflammation of the heart muscle, and pericarditis, inflammation of the tissue surrounding the heart.

The update followed a meeting Wednesday by the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices. The discussions concluded the heart warnings were necessary to add because data shows an increased risk of heart problems, particularly after the second dose.

"Today, the FDA is announcing revisions to the patient and provider fact sheets for the Moderna and Pfizer-BioNTech COVID-19 vaccines regarding the suggested increased risks of myocarditis and pericarditis following vaccination," the announcement reads.

Over 1,400 cases of myocarditis or pericarditis have been reported according to the U.S. Vaccine Adverse Event Reporting System (VAERS) and over eight thousand cases of irregular or increased heart rates have been reported, something not directly related to the FDA's heart warning. 

"The FDA and CDC are monitoring the reports, collecting more information, and will follow-up to assess longer-term outcomes over several months."