Caution: Some complementary agents or therapies may be useful for cancer patients; however, some may be harmful in certain situations. MD Anderson Cancer Center cautions patients to consult with their oncologist before attempting to use the agents or therapies described on these pages. Inclusion of an agent, therapy or resource on this CIMER Web site does not imply endorsement by MD Anderson Cancer Center.
- Review is based upon articles published as of 4/30/2006
- Information on the scientific basis of essiac therapy is provided in the Detailed Scientific Review
Essiac is not one but several herbs combined and steeped in water to form a tea. Some essiac teas include four herbs: burdock root, the inner bark of slippery elm, leaves of sheep sorrel and the root of Turkish rhubarb. Other essiac teas also include blessed thistle, red clover, kelp and watercress. Essiac teas are promoted for general health benefits, strengthening of the immune system, improving appetite, relieving pain and improving overall quality of life although anti-cancer affects have also been proposed.
Some laboratory and animal studies of individual essiac herbs have reported evidence of effectiveness in antioxidation, estrogen site binding competition, genetic protection, immune stimulation, anti-cell proliferation, laxative and bile stimulating activities. Some laboratory studies of combined herbal formulas have reported weak anti-proliferation effects on human cancer cells and stimulation of normal animal immune cells, but results have been inconsistent and some have occurred at higher concentrations than recommended or achievable for people.
No human clinical trials of essiac teas have been identified. (Reports of trials in China have not been confirmed in either the Chinese or the English published literature.) A phase II trial in collaboration with the British Columbia Cancer Agency was discontinued apparently due to difficulties in enrolling patients.
Providers recommend 30 ml (1 oz.) one to three times per day. People taking higher doses have reported diarrhea, constipation, nausea and fatigue.
How it is taken
Providers recommend drinking the tea on an empty stomach two hours before or after meals.
Some essiac herbs have laxative effects and allergic reactions from skin contact with individual herbs have occurred. The Canadian review of four essiac herbs concluded that serious side effects are unlikely when used as directed. A survey of consumers reported 6.6% who experienced diarrhea, constipation, nausea and fatigue, but 11.4% of these had exceeded the recommended dose.
Reports in 1985 of atropine poisoning from burdock were traced to contamination with belladonna (another herb) during harvesting. One case has been reported of prolonged toxic effects of chemotherapy due to reduced clearance of the drug in a patient consuming an essiac tea.
To avoid potential interactions, be sure to let your health care provider know if you use this or any other type of complementary therapy.
Authors and Editors
Nancy C. Russell, Dr.P.H., senior health education specialist, Integrative Medicine Program Education Component
Reviewers and editors:
Mary Ann Richardson, Dr.P.H., director, former University of Texas Center for Alternative Medicine
Stephen P. Tomasovic, Ph.D., senior vice president for academic affairs