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  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. Later that year, a new company was formed to manufacture and distribute this proprietary herbal mixture. Reviewed in 
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