Silychristin is one of 3 flavonolignan isomers in Silymarin mixture, isolated from the fruits of Silybum Sarianum, also known as milk thistle. Silymarin is one of the most widely used phytochemicals due to its extensive therapeutic properties in ancient and modern times. Its hepatoprotective properties is very well established. It is known that Silymarin is an antioxidant and reduces free radical production. It inhibits toxin binding to hepatocytes and was shown to reduce liver injury caused by various agents such as acetaminophen, mycotoxins, bacterial toxins, alcohol and more. Various studies demonstrated protective effects of silymarin not only against hepatotoxic agents but also against nephrotoxic, cardiotoxic and neurotoxic agents. Furthermore, Silymarin was found to inhibit ROS formation and to protect pancreatic β-cells from oxidative stress mediated destruction. An inhibitory effect of silychristin (10-100μM) on the arachidonic acid metabolism by cyclooxygenase (COX) in blood platelets was discovered. This suggests Silychristin can serve as an antiplatelet and anti-inflammatory agent. Interestingly, Silychristin was also found to inhibit the thyroid hormone transporter (MCT8) with IC50 of approximately 100 nM in MDCK1 cells. This data indicate that Silychristin could block the uptake of thyroid hormone.