Commentary on black cohosh for the treatment of menopausal symptoms

Abstract

Black cohosh as a possible treatment for menopausal symptoms reflects an increasing interest in the use of non-conventional or "alternative" medicines for amelioration of many disorders. However, it has often been difficult to distinguish between the purported benefits of herbal medicines and vitamins from the effects associated with a variety of placebos. To promote research in this area, an Office of Alternative Medicine was established at the National Institutes of Health in 1992. The Institute of Medicine (IOM) published a report on Complementary and Alternative Medicine in 2005 1 . Given the popularity of alternative medicines, objective examination of the effectiveness of these remedies as well as the possible interactions with conventional prescription medications is very important. The IOM recommended that "the same principles and standards of evidence of treatment effectiveness apply to all treatments, whether currently labeled as conventional medicine or complementary and alternative medicines. Implementing this recommendation requires that investigators use and develop as necessary, common methods, measures, and standards for the generation and interpretation of evidence necessary for making decisions about the use of complementary and alternative medicines and conventional therapies".In this context, the report by Reame et al 2 in this issue of Menopause on the effects of black cohosh on LH pulse frequency, estradiol levels, hot flashes and brain activation patterns measured by Positron Emission Tomography (PET) is a potentially valuable contribution to an often contradictory and inconclusive literature on alternative medicines for treatment of menopausal symptoms 3 . The rhizome of the black cohosh (Cimicifuga racemosa) is thought to contain estrogen-like compounds and to offer a natural alternative to estrogen therapy. One major finding was that 12 weeks of treatment with a commercial preparation of black cohosh (Remifemin, 40 mg/day) in 6 menopausal women did not change the pulse frequency of luteinizing hormone (LH) or levels of estrogen from pre-treatment baseline levels. No significant changes in the average number of hot flashes were detected. This was an open trial in a small sample of menopausal women and there was no placebo control treatment. However, this finding is consistent with previous reports that black cohosh had no discernable effect on the vaginal epithelium, endometrium, LH, FSH or estradiol during one year of treatment in a double-blind, placebo-controlled trial in women with vasomotor symptoms 4 . Similarly, a double-blind, cross-over trial comparing 4 weeks of black cohosh treatment with placebo did not detect any effect on the incidence of hot flashes 5 . A one year, double-blind, placebocontrolled trial reached similar conclusions 6 . There are several reports of liver toxicity associated with black cohosh treatment 7-10 as well as transient gastrointestinal disturbances and headache 11 . Given the apparent lack of efficacy of black cohosh as an estrogen substitute for the ...

Advances in the Treatment of Menopausal Symptoms

“…Case reports of acute liver disease have been reported [156,177]. Mello, in an editorial in Menopause , stated that since no objective effect on estrogen levels, luteinizing hormone pulse frequency or hot flashes have been found with black cohosh, the potential risks with long-term use appear to outweigh the benefits for treatment of menopausal symptoms [178].…”

Effect of Isopropanolic Cimicifuga racemosa Extract on Uterine Fibroids in Comparison with Tibolone among Patients of a Recent Randomized, Double Blind, Parallel‐Controlled Study in Chinese Women with Menopausal Symptoms

“…This herb was used traditionally and for some decades iCR has been available as herbal medicinal product for alleviating menopausal symptoms such as hot flushes, night sweats, and associated sleep impairments [ 5 ]. iCR is not a so-called phytoestrogen, it does not have direct estrogenic effects [ 9 ], and it does not interfere with gynecological hormones [ 7 ] and LH pulse frequency in vivo [ 10 ]. Recent studies showed the reason why iCR could relieve neuroendocrine system symptoms such as hot flushes and others may be due to the effect on serotonin pathways [ 11 ] and the endogenous opioid system [ 12 ].…”

Bioassay-guided evaluation of Dioscorea villosa – an acute and subchronic toxicity, antinociceptive and anti-inflammatory approach

“…Such ethnic knowledge of the herbal has been largely used to provide support for the production of medicines in order to improve the life quality of the populations [1,2]. In Brazil, the use of products derived from medicinal plants is regulated by the National Agency of Sanitary Surveillance through the law of herbal medicines (RDC n° 14 of 31/03/2010), which aims to ensure the quality of herbal products [3].…”

“…These adverse reactions have propelled the search for safer alternative therapies in the last decades, such as the use of herbal products [1,2,7]. …”