President Donald Trump announced the Food and Drug Administration approved "emergency use" of blood plasma from COVID-19 survivors to treat other patients.
However, the World Health Organization is cautioning that it is still considered experimental therapy.
In the early days of the coronavirus pandemic, convalescent plasma was one of the first treatments to give people hope. It involves extracting plasma from the blood of people previously infected with the coronavirus.
"This plasma is particularly antibody-rich," said Dr. Michael Daignault, emergency medicine specialist with Providence St. Joseph Medical Center.
The hope is that injecting the amber-colored liquid into COVID-19 patients will help them recover, but the data is limited. A Mayo Clinic study suggests if patients receive convalescent plasma within three days of diagnosis, they had a 9% start mortality rate compared to 12% at four days or later.
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"The problem with this study is that there was no comparison group that would just get the standard care. It's what we would call the placebo arm," Daignault said.
Despite the lack of randomized controlled studies, Trump announced that the FDA will allow emergency use of convalescent plasma, stating it can reduce the chances of dying by some 35%.
"I went hunting for where they got that statistic and I couldn't find it," Daignault said.
Daignault said the problem with authorizing emergency use for a therapy and then finding out it doesn't work later may undermine the public's trust.
And other experts point out rationing may become a problem since plasma depends on donations.
Daignault hopes solid research will drive more decisions when it comes to more treatments and drugs for COVID-19 patients.
"Look for the evidence for yourself and trust the scientists," he said, "Trust the doctors and the science-driven process."