Physicians don't make recommendations 'on whims': AMA

"Science and the evidence have to rule the day," Harris said in a live national address with the National Press Club.

"Physicians don't make treatment recommendations as you heard me say earlier on whims. There is a decision-making process that physicians go through for every treatment that we recommend and that should continue to hold through for COVID-19 and anything else we face in the future," she said.

The decades-old drug that President Donald Trump has persistently promoted as a potential weapon against COVID-19 has within a matter of weeks become a standard of care in areas of the United States hit hard by the pandemic - though doctors prescribing it have no idea whether it works.

Doctors and pharmacists from more than half a dozen large healthcare systems in New York, Louisiana, Massachusetts, Ohio, Washington and California told Reuters they are routinely using hydroxychloroquine on patients hospitalized with COVID-19. At the same time, several said they have seen no evidence that the drug, used for years to treat malaria and autoimmune disorders, has any effect on the virus.

Potential side effects of hydroxychloroquine include vision loss and heart problems. But doctors interviewed by Reuters say they are comfortable prescribing the drug for a short course of several days for coronavirus patients because the risks are relatively low and the therapies are inexpensive and generally available.

However, protocols directing how these drugs should be used vary from one hospital to another, including when to introduce them and whether to combine them with other drugs. In addition, some studies showing promise involve patients who took the therapies for mild or early-stage illness. Many of those people are likely to recover from the virus on their own.