Hesperetin is a phytoestrogen and flavanone found in citrus plants that exhibits analgesic, antinociceptive, anti-inflammatory, antioxidative, cardioprotective, anti-fibrotic, anticancer, and anti-metastatic activities. Hesperetin inhibits mechanical and thermal hyperalgesia and allodynia and decreases production of IL-6,IL-1β, and TNF-α in animal models. In vitro, hesperetin decreases Ca2+ influx by inhibiting L-type Ca2+ channels, inducing vasorelaxation. Additionally, hesperetin increases expression of catalase, glutathione, superoxide dismutase, and glutathione peroxidase and decreases expression of lipid peroxidase in vivo. In other animal models, this compound prevents cardiac hypertrophy, cardiac dysfunction, and fibrosis. Hesperetin also activates Notch1 signaling, induces differentiation, and inhibits cell migration and invasion in anaplastic thyroid cancer cells. In breast cancer cells, this compound decreases the mitochondrial membrane potential and increases cytochrome c release, caspase 7 activation, and PARP cleavage, inducing apoptosis.