Although many women coping with hot flashes and other distressing symptoms of menopause have turned to black cohosh supplements as a treatment alternative, a new review by the Cochrane Library finds no evidence that the herb is effective.
"I was a little surprised of the outcome of the review given the large number of perimenopausal women that use the herb across the globe for the management of menopausal symptoms, as well as the many manufacturers and therapists that promote the herb for this purpose," said lead reviewer Matthew Leach, Ph.D., a research fellow in the School of Nursing & Midwifery at the University of South Australia.
Leach and his co-reviewer evaluated 16 studies involving 2,027 menopausal women. Study participants used an average daily oral preparation of 40 mg of black cohosh for an average of 23 weeks. Treatments for randomly assigned comparison groups included using placeboes, hormone therapy, red clover, or antidepressants.
The reviewers found there was insufficient evidence to support the effectiveness of black cohosh for menopausal symptoms. There was no significant difference between it and the placebo groups in changing hot flash frequency. Compared to black cohosh, hormone therapy significantly reduced hot flash frequency.
"I have many women patients who have tried black cohosh," said Brent A. Bauer, M.D., director of the Complementary and Integrative Medicine Program at the Mayo Clinic in Minnesota. "I would say the response seems to roughly fall into three camps: those that get a pretty noticeable improvement in symptoms and continue to use it long term, those that get some improvement but not enough to get enthusiastic about it, and those that try it and perceive no benefit at all."
Leach MJ, Moore V. Black cohosh (Cimicifuga spp.) for menopausal symptoms. Cochrane Database of Systematic Reviews 2012, Issue 9.