The popular herb black cohosh reduces hot flashes and other symptoms associated with menopause in most published clinical trials, said the American Botanical Council (ABC), a leading nonprofit herbal science organization.

ABC was responding to a press release summarizing an unpublished double-blind, placebo-controlled clinical trial on 132 women conducted by researchers at the Mayo Clinic. The researchers concluded that black cohosh pills used in their trial did not provide any noticeable benefit for menopause symptoms when compared to placebo.

ABC stressed that there are numerous weaknesses and problems with the trial. For example, a full report describing the trial’s results has not yet been completed and subjected to the necessary peer-review process required for publication in a reputable medical journal. Further, the trial was only four weeks in length, probably too short to measure any effect from the product tested, since most clinical trials on black cohosh have run for three to six months.

Another area of potential ambiguity in this trial is the black cohosh product employed. The researchers attempted to produce a replica of Remifemin®, the German black cohosh product with the most clinical research, because they could not acquire the patented product for the trial. It is not clear to what extent the researchers were actually successful in replicating an exact match of Remifemin.

At least 14 clinical trials on black cohosh preparations support their safety and efficacy in treating menopause-related symptoms, including hot flashes, perspiration and mood swings, according to Gail Mahady, PhD, Assistant Professor of Pharmacy Practice at the University of Illinois at Chicago, who has reviewed most of the research on black cohosh for a monograph for the World Health Organization.

American Botanical Council, May 18, 2005