I’ve previously reviewed the similarities between the flavonoid quercetin and the drug hydroxychloroquine, discussing the possibility of using quercetin in lieu of the drug against COVID-19. We’re now also starting to see quercetin mentioned more often in the scientific literature on COVID-19.

For example, a review article¹ published in the June 19, 2020, issue of Frontiers in Immunology highlights quercetin’s usefulness as a COVID-19 treatment, especially in conjunction with vitamin C. Quercetin is also featured in a review² of emerging COVID-19 research published in the Integrative Medicine journal. As reported by MedPage Today:³

“Quercetin … promotes SIRT2, which then inhibits the NLRP3 inflammasome assembly involved with COVID-19 infection, said Samuel F. Yanuck, DC, of the Program on Integrative Medicine at the University of North Carolina Chapel Hill School of Medicine, who co-authored a review⁴ of emerging research on the subject. It also plays a role in facilitating zinc transportation across lipid membranes, Yanuck said.

‘It’s not a bizarre or experimental substance and given it has these potential important biological roles, I think it’s worth being considered as part of an overall strategy,’ Yanuck told MedPage Today, adding that quercetin would need to be one part of a multifactorial treatment regimen …

COVID-19 has been associated with high levels of interleukin-6, depleted levels of interferons, and a cytokine storm that damages the body and is related to respiratory failure, said Ruben Colunga Biancatelli, MD, of Old Dominion University in Norfolk, Virginia, and first author of a paper on quercetin and vitamin C as a potential therapy for treating SARS-CoV-2 in Frontiers in Immunology.⁵