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NCI/PDQ^® Health professionals: Essiac/Flor Essence (PDQ®)

National Cancer Institute
Last Modified: July 22, 2010

TABLE OF CONTENTS

• Purpose of This PDQ® Summary

• Overview

• General Information

• History

• Laboratory/Animal/Preclinical Studies
  • Essiac
  • Flor Essence
  • The Individual Herbs of Essiac and Flor Essence

• Human/Clinical Studies
  • Essiac
  • Flor Essence

• Adverse Effects

• Overall Level of Evidence for Essiac and Flor Essence

• Changes to This Summary (07/22/2010)

• More Information

Purpose of This PDQ® Summary

This PDQ® cancer information summary for health professionals provides comprehensive, peer-reviewed, evidence-based information about the use of Essiac as a treatment in people with cancer. This summary is reviewed regularly and updated as necessary by the PDQ® Cancer Complementary and Alternative Medicine Editorial Board.

Information about the following is included in this summary:

• A brief history of Essiac research.
• Possible side effects of Essiac use.

This summary is intended as a resource to inform and assist clinicians and other health professionals who care for cancer patients. It does not provide formal guidelines or recommendations for making health care decisions.

Some of the reference citations in the summary are accompanied by a level of evidence designation. These designations are intended to help the readers assess the strength of the evidence supporting the use of specific interventions or treatment strategies. The PDQ® Cancer Complementary and Alternative Medicine Editorial Board uses a formal evidence ranking system in developing its level of evidence designations. These designations should not be used as a basis for reimbursement determinations.

This summary is also available in a patient version, which is written in less technical language.

Overview

This complementary and alternative medicine (CAM) information summary provides an overview of the use of Essiac and Flor Essence, which are proprietary herbal tea mixtures, as treatments in patients with cancer. The summary includes a brief history of the development of Essiac and Flor Essence; a review of laboratory, animal, and human studies; and possible side effects associated with Essiac and Flor Essence use.

This summary contains the following key information:

• Essiac and Flor Essence are herbal tea mixtures originally developed in Canada. There may be differences between Essiac and Flor Essence in their mixture content and effects.
• These products are marketed worldwide as dietary supplements.
• Proponents have claimed that Essiac and Flor Essence can help detoxify the body, strengthen the immune system, and fight cancer.
• Proponents of Essiac have further claimed that it can help relieve pain, improve quality of life, and reduce tumor size.
• Molecules with antioxidant, anti-inflammatory, anticancer, or immunostimulatory activity have been identified in the individual herbs in the Essiac and Flor Essence formulas.
• No controlled data are available from human studies to suggest that Essiac or Flor Essence can be effective in the treatment of patients with cancer.
• Some evidence suggests that Flor Essence may increase tumor formation in an animal model of breast cancer.

Many of the medical and scientific terms used in the summary are hypertext linked (at first use in each section) to the NCI Dictionary of Cancer Terms, which is oriented toward nonexperts. When a linked term is clicked, a definition will appear in a separate window. All linked terms and their corresponding definitions will appear in a glossary in the printable version of the summary.

Reference citations in some PDQ® CAM information summaries may include links to external Web sites that are operated by individuals or organizations for the purpose of marketing or advocating the use of specific treatments or products. These reference citations are included for informational purposes only. Their inclusion should not be viewed as an endorsement of the content of the Web sites, or of any treatment or product, by the PDQ® Cancer CAM Editorial Board or the National Cancer Institute.

General Information

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 3 4 5 6 7 8 9 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 3 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 further claim 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 section of this summary for more information). Reviewed in 2 3 4 9 13 14 15 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 3 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 (e.g., esophagitis, gastritis, duodenitis, and colitis) and as a treatment for cirrhosis of the liver. Reviewed in 2 However, no controlled data have been published in the peer-reviewed scientific literature to show the safety or the efficacy of Essiac or Flor Essence in patients with cancer or in patients with other health conditions (refer to the Human/Clinical Studies 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 3 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., 112 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. [PUBMED Abstract]
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. [PUBMED Abstract]
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. [PUBMED Abstract]
7. Reviews of Therapies: Herbal/plant therapies: Essiac. Houston, Tex: M.D. Anderson Cancer Center, 2002. Available online. [PUBMED Abstract]
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. [PUBMED Abstract]
9. Essiac. Toronto, Canada: Canadian Breast Cancer Research Alliance, 1996. [PUBMED Abstract]
10. The History of Essiac & Rene Caisse, Canada's Cancer Nurse. Kirkland, Canada: Altramed Health Products, 2001. Available online. [PUBMED Abstract]
11. Flora FlorEssence. Burnaby, Canada: Flora Manufacturing & Distributing Ltd. Available online. [PUBMED Abstract]
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. [PUBMED Abstract]
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]

History

Essiac was popularized in Canada during the 1920s, when the developer, a nurse from Ontario, began to advocate its use as a cancer treatment. In 1922, the developer obtained an herbal tea formula from a female breast cancer patient who claimed the mixture had cured her disease. Reviewed in 1 2 3 4 5 6 The patient reportedly received the formula from an Ontario Ojibwa Native American medicine man. The developer subsequently modified the formula, producing both injectable and oral forms of treatment. Reviewed in 2 3 4 5 6 7 8 9

From 1934 to 1942, the developer operated a cancer clinic in Bracebridge, Ontario, and dispensed Essiac free of charge. Reviewed in 10 In 1938, members of the Royal Cancer Commission of Canada visited the clinic and heard testimonials from patients who had been treated with the mixture. Reviewed in 4 8 The Cancer Commission concluded there was only limited evidence for the effectiveness of Essiac. After years of controversy, the developer closed the clinic in 1942 but continued to provide Essiac to patients until the late 1970s. Reviewed in 4 5 (Refer to the Human/Clinical Studies section of this summary for more information.)

From 1959 until the late 1970s, the developer collaborated with an American physician to conduct clinical and laboratory studies of Essiac and to promote its use. Reviewed in 4 8 This collaboration led to the development of the eight-herb formula now marketed as Flor Essence. None of the results of these collaborative studies were reported in peer-reviewed scientific journals.

In 1977, the developer provided a four-herb recipe for Essiac to a Canadian corporation. Reviewed in 6 8 In 1978, the corporation filed a preclinical new drug submission with the Canadian Department of National Health and Welfare (Health Protection Branch) and was given permission to conduct clinical studies of Essiac's safety and effectiveness in cancer patients. Reviewed in 4 5 6 8 9 In 1982, this permission was withdrawn when it was determined that the corporation had not fulfilled commitments to adequately control the manufacturing consistency of Essiac, to isolate and characterize active substances in the mixture, and to design and execute appropriate clinical trials. Reviewed in 4 5 6 During this period, restrictions were imposed on the promotion of Essiac as a cancer treatment, but the corporation was allowed to distribute it to cancer patients through their physicians under Canada's Emergency Drug Release Program (also called Health Canada's Special Access Programme). Reviewed in 8 While the preclinical new drug submission was in effect in Canada, the corporation filed an unsuccessful New Drug Application (NDA) with the U.S. Food and Drug Administration, seeking permission to market Essiac in the United States. Details of the NDA submission, which can be disclosed only by the corporation, have not been made public. Reviewed in 5 (Refer to the Human/Clinical Studies section of this summary for more information.)

In the early 1980s, the Canadian Department of National Health and Welfare (Bureau of Human Prescription Drugs) conducted a retrospective review of case summaries submitted by physicians whose patients had obtained Essiac under the Emergency Drug Release Program. Reviewed in 2 5 8 The Department found little evidence to suggest that Essiac was effective as a cancer treatment. (Refer to the Human/Clinical Studies section of this summary for more information.)

Also in the 1980s, the manufacturers of Essiac-like products began to market their formulations as health tonics and to avoid making claims of effectiveness in treating disease. Consequently, the mixtures were no longer subject to regulation as drugs. Reviewed in 4 Essiac is not currently available under Canada's Emergency Drug Release Program.

In 1995, the corporation that acquired the four-herb recipe for Essiac from the developer dissolved voluntarily. 1 Later that year, a new company was formed to manufacture and distribute this proprietary herbal mixture. 1 Reviewed in 6

References:

1. Essiac. Kirkland, Canada: Altramed Health Products, 2002. Available online. [PUBMED Abstract]
2. Tamayo C: Essiac for cancer. Alternative Therapies in Women's Health 2 (3): 19-23, 2000. [PUBMED Abstract]
3. Locock RA: Essiac. Can Pharm J 130: 18-9, 1997. [PUBMED Abstract]
4. Reviews of Therapies: Herbal/plant therapies: Essiac. Houston, Tex: M.D. Anderson Cancer Center, 2002. Available online. [PUBMED Abstract]
5. 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. [PUBMED Abstract]
6. LeMoine L: Essiac: an historical perspective. Can Oncol Nurs J 7 (4): 216-21, 1997. [PUBMED Abstract]
7. 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]
8. 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]
9. Essiac. Toronto, Canada: Canadian Breast Cancer Research Alliance, 1996. [PUBMED Abstract]
10. The History of Essiac & Rene Caisse, Canada's Cancer Nurse. Kirkland, Canada: Altramed Health Products, 2001. Available online. [PUBMED Abstract]

Laboratory/Animal/Preclinical Studies