The US Food and Drug Administration has ordered vaccine manufacturers Pfizer/BioNTech and Moderna to use expanded warning labels on their Covid-19 vaccines. The new labels will provide more information about the risk of a rare heart condition, myocarditis, after vaccination. This condition can also cause pericarditis, inflammation of the lining outside the heart.
The FDA’s move comes as research has shown that Covid-19 infection itself carries a higher risk of myocarditis or pericarditis than the vaccine does. However, studies have consistently found that mRNA Covid-19 vaccines are safe and effective.
According to the US Centers for Disease Control and Prevention, the risk of myocarditis is rare but possible after vaccination. The CDC has found that in 2020 through 2022, Covid-19 vaccinations showed a statistically significant increased risk of myocarditis. However, this risk was not observed with doses administered in subsequent years.
The new warning labels will expand on existing warnings about heart problems associated with the vaccines. Previously, the highest risk of these conditions was seen in males between ages 18 and 24 for Moderna’s vaccine, and 12 to 17 for Pfizer’s vaccine. The expanded labels will now warn males aged 16 to 25.
The FDA has also taken steps to limit Covid-19 vaccines for certain groups. As of the fall, only adults 65 and older or people with underlying conditions that put them at a higher risk for severe Covid-19 infection will be eligible for updated shots. The decision comes as some experts claim that there is not enough evidence to support regular Covid-19 vaccinations in healthy children and adults.
Source: https://edition.cnn.com/2025/05/21/health/fda-covid-vaccine-warning-heart-inflammation