Isorhamnetin is a natural flavonol aglycone that is the 3-methyl metabolite of quercetin . It has antioxidant activity and inhibits xanthine oxidase (IC50 = 0.40 µM).¹ Isorhamnetin also competitively inhibits the human multidrug and toxic compounds extrusion transporter 1 (Ki = 0.32 µM), which has an important role in the excretion of xenobiotics at the kidney and liver.² It has also been reported to potentiate the neurological actions of nerve growth factor, diminish the cardiotoxic impact of doxorubicin, and have beneficial anti-cancer effects.^3,4,5,6