Milk thistle has been used for centuries as an herbal medicine for the treatment of liver disease. The active constituent in milk thistle is silymarin, a mixture of three flavolignans. Silybin is the most biologically active flavonoid in silymarin. Therapeutically, milk thistle acts by protecting liver cells from toxic damage, boosting glutathione concentrations, and regenerating normal liver cells. Milk thistle is also a potent free radical scavenger. In humans, milk thistle has been used clinically for a number of conditions including alcoholic liver diseased, hepatitis, amanita mushroom poisoning, and skin disease. Silymarin has also shown to enhance liver detoxification by by inhibition of Phase I detoxification while enhancing glucuronidation. One of the most important aspects of this herb is that it slows down or even reverses the formation of fibrosis (scar tissue) in the liver. This is my main herbal treatment in liver disease.