encyclopedia

Yellow Dock Herb and Root

Scientific Names:
Rumex crispus L. [Fam. Polygonaceae]

Forms:
Aqueous extract of whole or cut dried herb or roots.

Traditional Usage:
– Anemia
– Anti-diarrhea
– Anti-inflammatory
– Antioxidant
– Bile Deficiency
– Blood Purification
– Cellular Regeneration
– Cleansing
– Constipation
– Detoxifying
– Digestive Disorders
– Diuretic
– Indigestion
– Laxative
– Liver Health Maintenance
– Psoriasis
– Scurvy
– Skin Disorders
– Spleen Deficiency
– Vascular Disorders

Overview:
Yellow Dock, Rumex crispus L. [Fam. Polygonaceae], otherwise known as curly dock, is very high in iron and is used by herbalists for treating anemia. It was traditionally used to nourish and detoxify the spleen and liver and cleanse the blood. The Iroquois of Canada traditionally cooked the young leaves of Rumex crispus as greens. Rumex crispus has been used traditionally to treat anemia, anthrax, diarrhea, eczema, fever, itch, leprosy, malaria, rheumatism, ringworm and tuberculosis. According to Dr. James Duke and Stephen Foster in Medicinal Plants (1990), herbalists often recommend the root tea for chronic skin disorders, enlarged lymph glands, skin sores, rheumatism, liver ailments and sore throats. Yellow dock is very similar in taste and composition to the closely related plant, sheep sorrel (Rumex acetosella), used in the popular healing teas Flor-Essence and Essiac. At low doses, most Rumex species are useful for treating diarrhea. The high tannin content of the infusion provides astringent action useful for treating diarrhea and excessive menstrual bleeding. However, Rumex teas consumed in higher doses act as laxatives due to the presence of anthraquinones that directly effect the neuromuscular tissue of the intestines, stimulate peristalsis, increase the mucous production of colonic mucosal cells and stimulate secretion of water into the intestinal lumen, thereby exerting a laxative effect. A comparison of the distribution of anthraquinones in 19 representative species of Rumex showed an identical profile between Rumex acetosella and Rumex acetosa and good similarity to R. crispus. Yellow dock contains several anthraquinones that are effective antioxidants and free radical scavengers. Anthraquinones can arrest the growth of ringworm and other fungi. Many Rumex species also contain a powerful antibacterial compound called rumicin, effective against Escherichia, Salmonella and Staphylococcus. Ethanol and ether extracts of yellow dock leaves have significant antimicrobial activities against Staphylococcus aureus and Bacillus subtilis.

Active Ingredients:
Yellow dock herb contains: anthraquinones including emodin, aloe emodin, chrysophanol, rhein, and physcion; rutin, flavone glycosides; vitamin C; many different carotenoids including beta-carotene, chlorophyll, organic acids (i.e., malic, oxalic, tannic, tartaric and citric) and phytoestrogens. Minerals include calcium; phosphorus; magnesium; potassium, and silicon, along with iron, sulphur, copper, iodine, manganese, and zinc. Yellow dock root contains: 2-4% anthraquinones including chrysophanol, emodin, nepodin and physcion (aglycones). Tannins such as Catechol (5%) (condensed-type). Other plant constituents documented include oxalic acid, oxalates, chrysophanic acid and a complex volatile oil (more than 60 components identified).

Suggested Amount:
Yellow dock can be taken as a tea with the recommended dosage of one to three cups per day, using one teaspoonful of dried aboveground herb or root per cup of boiling water. Newall et al. (1996) recommend using 2-4 grams of the dried root or by decoction three times daily. Liquid extract (1:1) in 25% alcohol) 2-4 mil, three times daily. Tincture (1:5 in 45% alcohol) 1-2 ml three times daily. [Newall CA, Anderson LA, and Phillipson JD. 1996. Yellow Dock. In Herbal Medicines. A Guide for Health Care Professionals. The Pharmaceutical Press, London, pp. 274].

Drug Interactions:
In large dosages, the anthraquinones-type laxative compounds may increase the action of other laxatives and so should not be taken at the same time.

Contraindications:
Yellow dock and other plants of the Polygonaceae family contain oxalates in their fresh and cooked leaves and are contraindicated in cases of kidney stones. These plants with a characteristic tart taste, including rhubarb, should not be eaten in quantity (just as a flavouring or spice in small amounts) because the oxalates may interfere with calcium metabolism in the body, especially in a calcium-poor diet. Dock, sorrel and rhubarb leaves contain enough oxalates and anthraquinones-type laxative compounds to cause poisoning and possibly even death if eaten in excessive amounts. One death has been reported for a man consuming a soup made with 500g of French sorrel (Rumex acetosa). Teas containing sheep sorrel (hot aqueous extracts of sorrel that do not contain any raw herb material) contain only trace amounts of oxalates, however manufactures of such teas should do routine testing to assure customers of safe levels. Large doses of yellow dock tea and/or concentrated extracts may also cause gastric disturbance, nausea and diarrhea due to anthraquinones-type laxative compounds.

Side Effects:
Large doses of yellow dock tea may cause gastric disturbance, nausea, and diarrhea due to anthraquinones-type laxative compounds. Large doses of the raw herb may even cause poisoning due to high oxalic acid and tannin content. One death has been reported for a man consuming a soup made with 500g of French sorrel (Rumex acetosa). Teas containing yellow dock (hot aqueous extracts of dock that do not contain any raw herb material) contain only trace amounts of oxalates, however manufactures of such teas should do routine testing to assure customers of safe levels.

References:

Duke JA. 1985. Rumex crispus L. In Handbook of Medicinal Herbs. CRC Press, Boca Raton, FL, pp. 414-415.

Fairbairn JW, and Muhtadi FJ. 1972. Chemotaxonomy of Anthraquinones in Rumex. Phytochemistry 11: 263-268.

Gunaydin K, Topcu G, Ion RM. 2002. 1,5-dihydroxyanthraquinones and an anthrone from roots of Rumex crispus. Nat Prod Lett. 2002 Feb; 16(1): 65-70.

Turner N, and Kuhnlein H. 1991. Traditional plant foods of Canadian indigenous peoples. Nutrition, botany and use. In Food and Nutrition in History and Anthropology Vol. 8. Gordon & Breach Science Publishers, Philadelphia, PA, p. 222.

Yildirim A, Mavi A, Kara AA. 2001. Determination of antioxidant and antimicrobial activities of Rumex crispus L. extracts. J Agric Food Chem. 2001 Aug; 49(8): 4083-9.