In 2004, the Emergency Use Authorization (EUA) program was established in 2004, when the Project BioShield Act, among other measures, permitted the FDA Commissioner to authorize the use of an unapproved medical product or an unapproved use of an approved medical product during a declared emergency involving a heightened risk of attack on the public or U.S. military forces, or a significant potential to affect national security.

Prior to the response to H1N1 in 2009, only two EUAs had been issuedﾗone for a medication for the prevention of inhalation anthrax (the authorization has since been terminated) and the second for antibiotic emergency kits for the postal model, which was issued in 2008.