CYP2C9 and COVID-19: Licorice is one of the most frequently involved herbs in these herbal formulae or preparations against COVID-19, increasing risk for HDIs for anti-COVID-19 drugs (Lyu et al., 2021), and has been reported to modulate several CYP isoforms in vitro, including CYP3A4, CYP2C9, and CYP2E1 (Wang et al., 2013).