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Essiac/Flor Essence (PDQ®): Integrative, Alternative, And Complementary Therapies - Health Professional Information [NCI]

This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http://cancer.gov or call 1-800-4-CANCER.

Overview

This cancer information summary provides an overview of the use of Essiac and Flor Essence, which are proprietary herbal tea mixtures, as treatments for people 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, reduce side effects, 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.

Reference citations in some PDQ cancer information summaries may include links to external websites 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 websites, or of any treatment or product, by the PDQ Integrative, Alternative, and Complementary Therapies Editorial Board or the National Cancer Institute.

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