Rumex crispus
Part Used: Dried root
Yellow Dock (Rumex crispus) is a perennial herb that prefers full sun and average soil, growing up to 4 feet high. Historically, Yellow Dock has been taken orally to treat respiratory conditions, because it contains tannins, which dry up secretions. It contains tannins which are chemicals that have an astringent effect—meaning that they shrink and tighten the top layers of skin or mucous membranes, to reduce secretions, relieve irritation, and improve tissue firmness. Therefore, Yellow Dock may help to lessen cold or allergy symptoms such as watery eyes, sinus congestion, and runny noses. It is a powerful blood purifier and astringent. It is used in treating all diseases of the blood and skin. It is very high in iron, making it useful for treating anemia. It nourishes the spleen and liver, detoxifies the liver, and cleanses and enriches the blood.
Yellow Dock is used extensively in the treatment of chronic skin complaints, especially psoriasis associated with constipation; and obstructive jaundice. The anthraquinones have a cathartic action on the bowel, but act in quite a mild way, possibly tempered by the tannin content. It promotes the flow of bile, and its action on the gallbladder gives it a role in the treatment of jaundice when this is due to congestion. The plant's high iron content makes it valuable for correcting anaemia. A compress can be used to help soothe itchy skin. The ointment is valuable for itching, sores, swellings and scabby eruptions. The root has laxative, alterative and mildly tonic action, and can be freely used as a tonic and laxative in rheumatism, bilious complaints and as an astringent in piles, bleedings of the lungs, etc. It is largely prescribed for diseases of the blood, from a spring eruption, to scurvy, scrofula and chronic skin diseases. It is also useful in jaundice and as a tonic to the stomach and the system generally.
References:
Drug Digest. http://www.drugdigest.org/DD/DVH/HerbsWho/0,3923,9060%7CYellow+Dock,00.html
Purple Sage Botanicals. http://www.purplesage.org.uk/profiles/yellowdock.htm
Botanical. Com. http://botanical.com/botanical/mgmh/d/docks-15.html