FDA Won’t Add “Black Box” Warning to COVID-19 Shots

• by Rishma Parpia

• Published December 22, 2025
• Risk & Failure Reports

 

 

 

News outlets have recently reported that the U.S. Food and Drug Administration (FDA) was considering adding a box warning (known for many years as a “Black Box” warning) to COVID-19 shots. A boxed warning appears prominently at the top of a drug’s prescribing information and represents the FDA’s strongest safety alert. The agency uses it to highlight risks such as death or severe or potentially disabling reactions that clinicians and patients must consider alongside a treatment’s benefits. In some cases, the warning signals that restricting a medicine’s use to certain groups may reduce the risk.^{1 2}

According to news reports, people familiar with internal FDA discussions said the agency reviewed whether existing warnings about rare side effects sufficiently informed the public. It was indicated that the discussions focused on known risks such as myocarditis and pericarditis, which have been observed primarily in younger vaccine recipients. Sources said the conversations were part of a broader evaluation of vaccine labeling rather than a finalized policy decision.³

Public health professionals responded to these speculations by noting that the FDA already discloses known vaccine risks through fact sheets and product labeling provided to clinicians and patients. They said the agency typically reserves black box warnings for drugs with well documented and frequent serious risks, which they said does not reflect the evidence related to COVID shots. They also claimed that the safety monitoring data showing that serious adverse reactions to COVID shots remain uncommon, undermining assertions that stronger labeling warnings are warranted based on current data.⁴

FDA Leadership Rejects Box Warning Reports

After the reports circulated, FDA commissioner Marty Makary, MD, MPH said the FDA reviewed the issue and decided the evidence did not support the most severe “black box” warning designation. He stated:

When it comes to the black box warning, we have no plans to put that on the COVID vaccine. The safety and epidemiology center within the FDA did recommend that. It was a recommendation formally put out. But some of our scientists and leadership, like Dr. Vinay Prasad, have said it may be different today than it was in the first year of COVID when the shot came out. Because when you have those two doses three months apart, that’s when you see the side effects go way up like myocarditis in young people.⁵

FDA Updated Heart Inflammation Warning for mRNA COVID Shots

In June 2025, the FDA updated the myocarditis and pericarditis warning in the prescribing information for the mRNA COVID shots Comirnaty and Spikevax to clarify that the highest observed risk occurred in males ages 12 through 24 years old. The agency said analyses of commercial health insurance claims from inpatient and outpatient settings showed an estimated unadjusted incidence of about eight cases per million doses within seven days of vaccination among people ages six months through 64 years, compared with about 27 cases per million doses among males ages 12 through 24 following the 2023–2024 mRNA shot formulation.⁶

The FDA also added follow-up information from a longitudinal retrospective observational study of hospitalized patients diagnosed with COVID shot–associated myocarditis. Most patients in the study had received two-doses of mRNA shots before diagnosis and cardiac magnetic resonance imaging commonly showed persistent abnormalities at a median follow-up of about five months after vaccination.

The FDA’s updated product insert labeling builds on myocarditis and pericarditis warnings that have been included in mRNA COVID shot information materials since 2021.⁷

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