Rumex crispus

Related Terms

Curled dock, curley dock, curly dock, Polygonaceae (family), Rumex crispus, Rumex obtusifolius, yellow dock root.

Background

Yellow dock is often described as helping strengthen the blood; however, very few laboratory or human studies have been conducted to confirm this traditional use.
Yellow dock is one of the original plants in the Native American anticancer herbal formula now known as Essiac?. In some versions of Essiac? yellow dock is substituted for the sheep's sorrel.
The roots have been taken internally to build healthy blood, protect the liver, or act as an antifungal or laxative. As a seed tea, yellow dock may heal mouth sores and help diarrhea. Externally, yellow dock has been used to dissolve lumps and as an antitumor and antifungal. Yellow dock root (herb and salad green) is an astringent that has been banned in Canada.

Evidence Table

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. GRADE *
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)
* Key to grades

A: Strong scientific evidence for this use
B: Good scientific evidence for this use
C: Unclear scientific evidence for this use
D: Fair scientific evidence for this use (it may not work)
F: Strong scientific evidence against this use (it likley does not work)

Tradition / Theory

The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Dosing

Adults (18 years and older)
There is no proven safe or effective dose for yellow dock in adults. Herbalists have recommended the roots and seeds daily for up to 12 months. As a tincture of the fresh roots, 10-60 drops has been used (20 drops, two or three times a day). A fresh root vinegar preparation (1-2 tablespoons or 30 milligrams) has also been used. Based on expert opinion, no more than one cup (250 milligrams) of the dried seed tea should be taken per day.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Interactions

Interactions with Drugs
Yellow dock may have estrogenic activity, although more research is needed to clarify the exact mechanism of action. Caution is advised when taking drugs with estogenic activity due to possible additive effects.
A fatal poisoning from yellow dock (Rumex crispus) occurred after ingestion of a large quantity of the fresh leaves as a salad vegetable. Pathological findings included liver and kidney damage, which may have been caused by the tannins found in the leaves. Caution is advised in patients with liver or kidney problems, or in patients who are taking drugs that affect the liver or kidneys.
Yellow dock contains anthraquinones. In theory, yellow dock may have additive effects with other laxative agents.
Yellow dock contains tannins and may increase the risk of side effects when taken with other agents that contain tannins.

Attribution

This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

Reig R, Sanz P, Blanche C, et al. Fatal poisoning by Rumex crispus (curled dock): pathological findings and application of scanning electron microscopy. Vet Hum Toxicol 1990;32(5):468-470.
Shen HD, Chang LY, Gong YJ, et al. [A monoclonal antibody against ragweed pollen cross-reacting with yellow dock pollen]. Zhonghua Min Guo.Wei Sheng Wu Ji.Mian.Yi.Xue.Za Zhi. 1985;18(4):232-239.