Yellow dock is small, leafy plant that grows wild in Europe and the United State. Also called curly dock, and closely related to rhubarb, the green leaves are commonly used in salads, while the yellow root has been used as a herbal folk-remedy for hundreds of years.
Ground up and brewed, yellow dock root makes a bitter-sweet tea or infusion that has been used by herbalists in the treatment of a variety of disorders, primarily to treat enlarged liver and to purify the blood. It was also thought a good remedy for syphilis, tuberculosis, gum disease and leprosy, but is no longer recommended for these serious disorders.
Modern herbalists will still occasionally recommend yellow dock tea as a treatment for the liver and gallbladder, though its mainly employed in the treatment of skin disorders and digestive ailments. There is virtually no research to support the use of yellow dock as an effective treatment for psoriasis or acne.
Yellow dock is known to contain tannin which is an astringent is mildly useful in the treatment of diarrhea and stomach distress, though in large enough doses it may actually cause diarrhea. The root also contain several anthraquinone glycosides that researchers recognize as being responsible for its undisputed laxative effect.
Yellow dock is generally considered to be mildly effective as a laxative, and not very effective for much more. Side effects of excess consumption of yellow dock include excessive urination, nausea and diarrhea.