Researchers say clinical trials should be done to see whether the already FDA-approved drug should be used to prevent, or as an early treatment for, COVID-19.

If there are infection-fighting effects, they can’t be gotten from recreational use of pot. emphasize that “COVID-blocking effects of CBD were confined Researchers strictly to high purity, high concentrations of CBD.”

“Closely related cannabinoids such as CBDA, CBDV and THC, the psychoactive element enriched in marijuana plants, did not have the same power,” the statement said. “In fact, combining CBD with equal amounts of THC actually reduced the efficacy of CBD. “

At first, researchers looked at CBD to calm the dramatic and damaging symptoms of COVID.

“CBD has anti-inflammatory effects, so we thought that maybe it would stop the second phase of COVID infection involving the immune system, the so-called ‘cytokine storm.’ Surprisingly, it directly inhibited viral replication in lung cells,” said Marsha Rosner, a senior author of the study.

What they found was, although CBD did not affect the ability of SARS-CoV-2 to enter the cell, it was effective at blocking replication early in the infection cycle and six hours after the virus had already infected the cell.

The study was supported by a BIG Vision grant from the University of Chicago, the National Institutes of Health and the Leona M. & Harris B. Helmsley Charitable Trust.

This story first appeared in our sister publication, Crain’s Chicago Business.