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[0] Essiac [1] Antioxidant, Immune enhancing, Stimulate secretion of GI motility. [2] Increased stool, flu-like symptoms, slight headaches, swollen glands. [4] Not recommended due to lack of evidence to support claims. [3] 
It should be avoided with certain chemotherapy agents and with radiation therapy. Data has shown stimulation of breast cancer cells. There are multiple potential interactions with chemotherapy due to its effects on the liver metabolism of some of these agents.
Help or Harm? Nutritional supplements and cancer treatment often don't mix | University of Michigan Comprehensive Cancer Center
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