The FDA is drawing up plans to put a ‘black box’ warning on Covid vaccines, the agency’s most serious warning over potential side effects, reports suggest.

The move was revealed to CNN by two people familiar with the matter, who spoke on condition of anonymity because they were not authorized to speak to the media.

A black box warning, which appears at the top of prescribing information, is placed on drugs or vaccines to highlight major risks such as serious side effects or restrictions.

Sources did not specify what the warning would contain, or whether it would apply to only mRNA Covid vaccines or all Covid vaccines.

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