Essiac and Flor•Essence are proprietary herbal tea mixtures produced by different manufacturers. Essiac is reported to contain four herbs: burdock root (Arctium lappa L.), Indian rhubarb root (Rheum palmatum L., sometimes known as Turkish rhubarb), sheep sorrel (Rumex acetosella L.), and the inner bark of slippery elm (Ulmus fulva Michx. [synonym Ulmus rubra]).[1] Reviewed in [2-10] Flor•Essence is reported to contain the same four herbs as Essiac, plus four potentiating herbs: watercress (Nasturtium officinale R.Br.), blessed thistle (Cnicus benedictus L.), red clover (Trifolium pratense L.), and kelp (Laminaria digitata [Hudson] Lamx.).[11] Reviewed in [2-4,7]

The manufacturers of Essiac and Flor•Essence both claim they market the original herbal mixture promoted by the developer.[1,11] Although only one company manufactures Flor•Essence,[11] several companies produce and market Essiac-like products. Reviewed in [2,3,10] This summary contains information about the trademarked mixtures only and differentiates between the two products wherever possible. Essiac and Flor•Essence may vary in their mixture content and effects.[12]

Essiac and Flor•Essence are said to detoxify the body and strengthen the immune system.[1,11] Reviewed in [4,6,7,9] Proponents of Essiac claim further that it helps relieve pain, improves overall quality of life, may reduce tumor size, and may prolong the survival of patients with various types of cancer. Reviewed in [4,7,9] The individual herbs in the Essiac and Flor•Essence formulas have been shown to contain molecules that have anticancer, anti-inflammatory, antioxidant, or immunostimulatory activity (refer to the Laboratory/Animal/Preclinical Studies ¹ section of this summary for more information). Reviewed in [2-4,9,13-16] It is said that the benefits of Essiac and Flor•Essence are dependent on the presence of the constituent herbs in the correct proportions. Reviewed in [2-4,9] In 2004, a mixture of the Essiac herbs showed a decreased proliferation of a prostate cancer cell line.[17] (Refer to the Laboratory/Animal/Preclinical Studies section of this summary for more information.)

Although the use of Essiac and Flor•Essence is generally associated with cancer treatment, both products have been used to treat other health conditions. Essiac has reportedly been used to control diabetes and to treat acquired immunodeficiency syndrome. Reviewed in [6] Flor•Essence has reportedly been studied in Russia as a treatment for chronic gastrointestinal diseases (i.e., esophagitis, gastritis, duodenitis, and colitis) and as a treatment for cirrhosis of the liver. Reviewed in [2] No controlled data have been published in the peer-reviewed scientific literature, however, to show the safety or the efficacy of Essiac or Flor•Essence in patients with cancer or these other health conditions (refer to the Human/Clinical Studies ² section of this summary for more information).

Essiac and Flor•Essence are sold worldwide as health tonics or herbal dietary supplements.[1,11] Reviewed in [2-4,10] In the United States, health tonics and dietary supplements are regulated as foods, not drugs. Therefore, premarket evaluation and approval by the U.S. Food and Drug Administration (FDA) are not required, and specific disease treatment or prevention claims are not allowed. Because health tonics and dietary supplements are not formally inspected for manufacturing consistency, there may be considerable variation from lot to lot, and there is no guarantee that ingredients identified on product labels are present at all or are present in the specified amounts. The FDA has not approved the use of either Essiac or Flor•Essence for the treatment of patients with cancer or any other medical condition.

To conduct clinical drug research in the United States, researchers must file an Investigational New Drug (IND) application with the FDA. An IND application must also be made for clinical evaluation of dietary supplements as agents for the treatment or prevention of disease. The FDA’s IND process is confidential, and the existence of an IND application can be disclosed only by the applicants. To date, no investigator has announced filing an IND application to study either Essiac or Flor•Essence in the treatment of patients with cancer.

Essiac and Flor•Essence are administered orally in the form of herbal teas.[1,11] Reviewed in [4,6,8,9,18] Originally, an extract of one of the herbs (not specified) was administered to cancer patients by intramuscular injection at or near tumor sites, and the other herbs were administered orally as a tea. Reviewed in [4,8,9,18]

Only minimal information about dose and schedule of administration is freely available from the manufacturer of Essiac.[1] According to the manufacturer, the dose will vary, depending on the reason for ingestion; the manufacturer’s recommended schedules of administration assume a 12-week program of uninterrupted use.[1] Although Essiac is said to be safe for pets, no information is given about its safety in children.[1]

The manufacturer of Flor•Essence states that adults may consume from 30 to 360 mL (i.e., 1–12 fl oz) of Flor•Essence tea a day, depending on individual requirements, and that it may be used on an ongoing basis.[11] The manufacturer also suggests that Flor•Essence may be safely consumed by infants and children, but its use by pregnant women and nursing mothers is not recommended.[11] The promotion of mammary tumors observed in a rat model of breast cancer raises the theoretical concern that Flor•Essence may impact normal mammary ductal development during childhood, thereby raising concern about its use at this time.[19]

The manufacturers of Essiac and Flor•Essence both state these products can be used in conjunction with other cancer treatments.[1,11] Nonetheless, some proponents of Essiac have recommended that no additional anticancer therapy (such as chemotherapy or radiation therapy) be undertaken while patients are being treated with the mixture. Reviewed in [8] The purported rationale for this statement is that conventional anticancer treatments may alter immune system function and prevent Essiac from working effectively. Reviewed in [8] As indicated previously, no evidence has been reported in the peer-reviewed scientific literature to show that Essiac is an effective treatment for patients with cancer.

References

1. Essiac. Kirkland, Canada: Altramed Health Products, 2002. Available online. ³ Last accessed March 07, 2008. 
   
   
2. Tamayo C, Richardson MA, Diamond S, et al.: The chemistry and biological activity of herbs used in Flor-Essence herbal tonic and Essiac. Phytother Res 14 (1): 1-14, 2000.  [PUBMED Abstract]
   
   
3. Tamayo C: Essiac for cancer. Alternative Therapies in Women's Health 2 (3): 19-23, 2000. 
   
   
4. Kaegi E: Unconventional therapies for cancer: 1. Essiac. The Task Force on Alternative Therapies of the Canadian Breast Cancer Research Initiative. CMAJ 158 (7): 897-902, 1998.  [PUBMED Abstract]
   
   
5. Ernst E, Cassileth BR: How useful are unconventional cancer treatments? Eur J Cancer 35 (11): 1608-13, 1999.  [PUBMED Abstract]
   
   
6. Locock RA: Essiac. Can Pharm J 130: 18-9, 1997. 
   
   
7. Reviews of Therapies: Herbal/plant therapies: Essiac. Houston, Tex: M.D. Anderson Cancer Center, 2002. Available online. ⁴ Last accessed March 07, 2008. 
   
   
8. Herbal treatments. In: US Congress, Office of Technology Assessment.: Unconventional Cancer Treatments. Washington, DC: U.S. Government Printing Office, 1990. OTA-H-405, pp 71-5. Also available online. ⁵ Last accessed March 07, 2008. 
   
   
9. Essiac. Toronto, Canada: Canadian Breast Cancer Research Alliance, 1996. 
   
   
10. The History of Essiac & Rene Caisse, Canada's Cancer Nurse. Kirkland, Canada: Altramed Health Products, 2001. Available online. ⁶ Last accessed March 07, 2008. 
    
    
11. Flora Flor•Essence®. Burnaby, Canada: Flora Manufacturing & Distributing Ltd. Available online. ⁷ Last accessed March 07, 2008. 
    
    
12. Cheung S, Lim KT, Tai J: Antioxidant and anti-inflammatory properties of ESSIAC and Flor-Essence. Oncol Rep 14 (5): 1345-50, 2005.  [PUBMED Abstract]
    
    
13. Franke AA, Cooney RV, Custer LJ, et al.: Inhibition of neoplastic transformation and bioavailability of dietary flavonoid agents. In: Manthey JA, Buslig BS, eds.: Flavonoids in the Living System. New York, NY: Plenum Press, 1998. Advances in Experimental Medicine and Biology, 439, pp 237-48. 
    
    
14. Waladkhani AR, Clemens MR: Effect of dietary phytochemicals on cancer development (review) Int J Mol Med 1 (4): 747-53, 1998.  [PUBMED Abstract]
    
    
15. de Witte P: Metabolism and pharmacokinetics of anthranoids. Pharmacology 47 (Suppl 1): 86-97, 1993.  [PUBMED Abstract]
    
    
16. Campbell MJ, Hamilton B, Shoemaker M, et al.: Antiproliferative activity of Chinese medicinal herbs on breast cancer cells in vitro. Anticancer Res 22 (6C): 3843-52, 2002 Nov-Dec.  [PUBMED Abstract]
    
    
17. Ottenweller J, Putt K, Blumenthal EJ, et al.: Inhibition of prostate cancer-cell proliferation by Essiac. J Altern Complement Med 10 (4): 687-91, 2004.  [PUBMED Abstract]
    
    
18. LeMoine L: Essiac: an historical perspective. Can Oncol Nurs J 7 (4): 216-21, 1997.  [PUBMED Abstract]
    
    
19. Bennett LM, Montgomery JL, Steinberg SM, et al.: Flor-Essence herbal tonic does not inhibit mammary tumor development in Sprague Dawley rats. Breast Cancer Res Treat 88 (1): 87-93, 2004.  [PUBMED Abstract]
    
    

Glossary Terms

A disease caused by human immunodeficiency virus (HIV). People with acquired immunodeficiency syndrome are at an increased risk for developing certain cancers and for infections that usually occur only in individuals with a weak immune system. Also called AIDS.

Having to do with reducing inflammation.

A substance that protects cells from the damage caused by free radicals (unstable molecules made by the process of oxidation during normal metabolism). Free radicals may play a part in cancer, heart disease, stroke, and other diseases of aging. Antioxidants include beta-carotene, lycopene, vitamins A, C, and E, and other natural and manufactured substances.

A plant whose leaves, stems, and flowers have been used in some cultures to treat certain medical problems. Blessed thistle may have anti-inflammatory and anticancer effects. The scientific name is Cnicus benedictus. Also called cardin, holy thistle, spotted thistle, and St. Benedict's thistle.

A plant whose seeds and root have been used in some cultures to treat certain medical problems. It may have antioxidant effects. The scientific name is Arctium lappa. Also called happy major and lappa.

A term for diseases in which abnormal cells divide without control. Cancer cells can invade nearby tissues and can spread to other parts of the body through the blood and lymph systems. There are several main types of cancer. Carcinoma is cancer that begins in the skin or in tissues that line or cover internal organs. Sarcoma is cancer that begins in bone, cartilage, fat, muscle, blood vessels, or other connective or supportive tissue. Leukemia is cancer that starts in blood-forming tissue such as the bone marrow, and causes large numbers of abnormal blood cells to be produced and enter the blood. Lymphoma and multiple myeloma are cancers that begin in the cells of the immune system. Central nervous system cancers are cancers that begin in the tissues of the brain and spinal cord.

Treatment with drugs that kill cancer cells.

A disease or condition that persists or progresses over a long period of time.

A type of chronic, progressive liver disease in which liver cells are replaced by scar tissue.

A type of research study that tests how well new medical approaches work in people. These studies test new methods of screening, prevention, diagnosis, or treatment of a disease. Also called clinical trial.

Inflammation of the colon.

A currently accepted and widely used treatment for a certain type of disease, based on the results of past research. Also called conventional therapy.

To make something less poisonous or harmful. It may refer to the process of removing toxins, poisons, or other harmful substances from the body.

Any of several diseases in which the kidneys make a large amount of urine. Diabetes usually refers to diabetes mellitus in which there is also a high level of glucose (a type of sugar) in the blood because the body does not make enough insulin or use it the way it should.

A product that is added to the diet. A dietary supplement is taken by mouth, and usually contains one or more dietary ingredient (such as vitamin, mineral, herb, amino acid, and enzyme). Also called nutritional supplement.

The amount of medicine taken, or radiation given, at one time.

Inflammation of the duodenum (the first part of the small intestine that connects to the stomach).

Inflammation of the esophagus (the tube that carries food from the mouth to the stomach).

An herbal tea mixture that contains burdock root, Indian rhubarb root, sheep sorrel, and slippery elm bark. It has been claimed to remove toxins from the body, make the immune system stronger, relieve pain, control diabetes, treat AIDS, reduce tumor size, increase cancer survival, and improve quality of life. No clinical trial using Essiac in humans has been reported in a peer-reviewed, scientific journal, and the FDA has not approved the use of Essiac for the treatment of any medical conditions.

Liquid.

An agency in the U.S. federal government whose mission is to protect public health by making sure that food, cosmetics, and nutritional supplements are safe to use and truthfully labeled. The Food and Drug Administration also makes sure that drugs, medical devices, and equipment are safe and effective, and that blood for transfusions and transplant tissue are safe. Also called FDA.

Inflammation of the lining of the stomach.

Refers to the stomach and intestines. Also called GI.

Having to do with plants.

The complex group of organs and cells that defends the body against infections and other diseases.

A substance that increases the ability of the immune system to fight infection and disease.

The root of this plant has been used in some cultures to treat certain medical problems. It may have anti-inflammatory and anticancer effects. The scientific name is Rheum palmatum or Rheum officinale. Also called Chinese rhubarb, da-huang, rhubarb, and Turkish rhubarb.

Taking into the body by mouth.

Injection into muscle.

In clinical trials, refers to a drug (including a new drug, dose, combination, or route of administration) or procedure that has undergone basic laboratory testing and received approval from the U.S. Food and Drug Administration (FDA) to be tested in human subjects. A drug or procedure may be approved by the FDA for use in one disease or condition, but be considered investigational in other diseases or conditions. Also called experimental.

A researcher in a clinical trial or clinical study.

A type of seaweed. The stem-like parts of this plant have been used in some cultures to treat certain medical problems. It may have immunostimulatory and anticancer effects. The scientific name is Laminaria digitata.

A large organ located in the upper abdomen. The liver cleanses the blood and aids in digestion by secreting bile.

A measure of volume for a liquid. A milliliter is approximately 950 times smaller than a quart and 30 times smaller than a fluid ounce. A milliliter of liquid and a cubic centimeter (cc) of liquid are the same.

The smallest particle of a substance that has all of the physical and chemical properties of that substance. Molecules are made up of one or more atoms. If they contain more than one atom, the atoms can be the same (an oxygen molecule has two oxygen atoms) or different (a water molecule has two hydrogen atoms and one oxygen atom). Biological molecules, such as proteins and DNA, can be made up of many thousands of atoms.

By or having to do with the mouth.

A measure of weight (one-sixteenth pound) and volume (one-eighth cup).

In medicine, the effect of increasing the potency or effectiveness of a drug or other treatment.

Cancer that forms in tissues of the prostate (a gland in the male reproductive system found below the bladder and in front of the rectum). Prostate cancer usually occurs in older men.

The overall enjoyment of life. Many clinical trials assess the effects of cancer and its treatment on the quality of life. These studies measure aspects of an individual’s sense of well-being and ability to carry out various activities.

The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.

Trifolium pratense. A plant with flowers that has been used in some cultures to treat certain medical problems. It is being studied in the relief of menopausal symptoms and may have anticancer effects. Also called purple clover, Trifolium pratense, and wild clover.

A plant that has been used in some cultures to treat certain medical problems. It may have anticancer effects. The scientific name is Rumex acetosella. Also called dock and sorrel.

The inner bark of this plant has been used in some cultures to treat certain medical problems. It may have antioxidant effects. Also called gray elm, Indian elm, red elm, sweet elm, Ulmus fulva, and Ulmus rubra.

Parts of the flowering plant have been used in some cultures to treat certain medical problems. It may have anticancer effects. The scientific name is Nasturtium officinale. Also called Indian cress.