evidence: In response to the novel coronavirus disease 2019 (COVID-19) crisis, the Food and Drug Administration (FDA), via its Emergency Use Authorization (EUA) authority, initially provided, and then revoked, authorization for use of hydroxychloroquine for treating patients with COVID-19. This process was politically and scientifically contentious and illustrates central problems that can arise with emergency drug authorizations during crises. These problems include the authorization of potentially ineffective or unsafe therapeutics, the appearance of nonexpert political advocacy generating public pressure for product authorizations with questionable safety and efficacy, and the imposition of significant costs on the health of the public and on the credibility and influence of regulatory agencies such as the FDA. [...] Prior to the hydroxychloroquine EUA, interest in hydroxychloroquine as a COVID-19 treatment emerged in mid-March following the release of a controversial open-label nonrandomized French study that included 36 patients.5 Soon after, the Trump administration, followed by media outlets and segments of the US public, began championing hydroxychloroquine. On March 28, 2020, the FDA issued a letter granting an EUA "for emergency use of oral formulations of chloroquine phosphate and hydroxychloroquine sulfate for the treatment of" COVID-19.6 The letter did not describe the evidence underlying the decision. The FDA stated that the authorization was supported by recommendations "for treatment of hospitalized COVID-19 patients in several countries, and a number of national guidelines" based on "limited in-vitro and anecdotal clinical data in case series," presumably the French study and Chinese and Korean guidelines.6