"From Mayo Clinic website grudging admission of glaring truth: 'Hydroxychloroquine may be used to treat coronavirus (COVID-19) in certain hospitalized patients,'" Peter Navarro, who directed the Office of Trade and Manufacturing Policy under President Donald Trump, posted Sept. 24 on X, formerly known as Twitter. For those "who spread lies about hydroxy, this one's for u."

Mr. Navarro included a link to Mayo Clinic's hydroxychloroquine page that has since been taken down. COVID-19 information was added to Mayo's page for the drug as early as May 2020, the Post Bulletin reported. By mid-June of that year, the following statement was included: "(h)ydroxychloroquine should only be used for COVID-19 in a hospital or during clinical trials. Do not take any medicine that contains hydroxychloroquine unless prescribed by your doctor."

Early in the pandemic, the FDA authorized the emergency use of the antimalarial drug for treating COVID-19. But the agency revoked the authorization in June 2020, citing a lack of benefits and the risk of serious heart problems. President Trump said in May 2020 he was taking the drug to prevent getting the virus even after the FDA warned it shouldn't be used outside of hospital settings or clinical trials.