Early in 2007 the National Center for Complementary and Alternative Medicine distributed, through its NCCAM listserv, the results of a study on the use of black cohosh for hot flashes in menopause.1 The study conducted by Newton et al assigned subjects to 1 of 5 treatment groups comparing (1) black cohosh, (2) a multibotanical containing black cohosh, (3) a multibotanical plus counseling related to an enhanced soy diet, (4) hormone replacement therapy in the form of equine estrogen, and (5) placebo. The study concluded that only hormone replacement therapy resulted in a "clinically important decrease" in the frequency of hot flash symptoms and that the black cohosh herbal compounds used in the study were clinically ineffective. Responses to the report were numerous and pointed. They included critique concerning the prominence with which the report was released and critique of the study's methodological flaws, including the possible instability of the specific black cohosh product that was used and the small number of women in each of the 5 groups. Mark Blumenthal, Executive Director of the American Botanical Society, asserted that "the findings (of the black cohosh study) were at odds with existing evidence about black cohosh."
Nurse practitioners and many other providers often recommend blackcohosh to menopausal women experiencing vasomotor symptoms. Many women find black cohosh on their own as they search for safer substitutes for hormonal replacement therapy. In light of this latest report and the controversy surrounding it, this issue of Holistic Nursing Practice's feature on herbals and supplements discusses black cohosh, its derivation, history, pharmacology, uses, and contraindications. The results of this most recent study on black cohosh flies in the face of evidence on Remifemin, the most clinically researched black cohosh product available in Europe.2
The need for regulation of dietary and herbal supplements in the United States is long overdue, not only to protect the public from harm but also to endorse safe and efficacious products. In 2003, Eastman3 called for new legislation to define and regulate dietary supplements with at least the same rigor with which over-the-counter medicines are regulated.
Americans spend at least $17 billion per year on dietary supplements and at least 40% of older Americans use botanicals or herbal products in an effort to maintain and improve health. Therefore, the government owes the public some form of regulation of these products to ensure potency and efficacy, to warn of possible side effects and contraindications, and to gather data on adverse reactions. The manufacturers of biologically active substances such as botanical and dietary supplements cannot claim clinical efficacy and harmlessness at the same time. And, responsible manufacturers will welcome regulation for the health and safety of the public. So the next time you prescribe or recommend an herbal product to a patient, be certain that you have reviewed the evidence on efficacy. We owe patients and clients nothing less.
Gloria Ferraro Donnelly, PhD, RN, FAAN
Editor-in-Chief
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