The Food and Drug Administration (FDA) has authorized revisions to the fact sheets for the Moderna and Pfizer-BioNTech COVID-19 vaccines to include information related to the risk of myocarditis and pericarditis after vaccination.

The fact sheets for both vaccines have been updated following an extensive review by the Centers for Disease Control and Prevention (CDC)’s Advisory Committee on Immunization Practices. According to the CDC, more than a thousand cases of myocarditis and pericarditis following mRNA COVID-19 vaccination have been reported to the Vaccine Adverse Event Reporting System since April 2021. The confirmed cases were mostly in male adolescents and individuals 16 years of age and older and occurred more often after the second dose. 

The Fact Sheet for Healthcare Providers Administering Vaccine now includes a warning stating that reports of adverse events following the use of the Moderna or Pfizer-BioNTech COVID-19 vaccine suggest increased risks of myocarditis and pericarditis, particularly following the second dose. Typically, the onset of symptoms occurs within a few days after vaccination. For healthcare providers, the decision to administer a vaccine to an individual with a history of myocarditis or pericarditis should be made based on the individual’s clinical circumstances.

The CDC continues to recommend COVID-19 vaccination for all individuals 12 years of age and older.


  1. Coronavirus (COVID-19) update: June 25, 2021. [press release]. Silver Spring, MD: US Food and Drug Administration; June 25, 2021. 
  2. US Centers for Disease Control and Prevention. Myocarditis and pericarditis following mRNA COVID-19 vaccination. Updated June 23. Accessed June 30, 2021.