Quercetin is a great flavonoid for many reasons: It’s a known anti-histamine. It’s considered essential in anti-aging protocols. It modulates DNA methylation and epigenetic expression. It also may drop blood cholesterol through inhibition of PCSK9. McGill scientists looking at quercetin’s ability to lower cholesterol are also looking at it as a potential antiviral agent. A study is now underway in China looking at quercetin and COVID19. While there are online resources recommending quercetin now, and you may choose to prescribe it to your COVID19 patients or for prevention, know that outcome of the COVID19 trial will not be available for months.