Black COHOSH
Place in Therapy
Although some older studies suggested that black cohosh might be effective in reducing vasomotor symptoms of menopause and perimenopause, more recent, larger randomized controlled trials (RCT) have shown the effect of black cohosh no different than placebo. A 2012 Cochrane meta-analysis looked at 15 RCTs and concluded that, although there was considerable heterogeneity in the trials, black cohosh was not any better than placebo[1]. This result confirmed the conclusion of a 2008 systematic review by Borrelli[2]. Natural Standard lists black cohosh as level C, meaning unclear or conflicting evidence[3].
A second 2008 systematic review by Borrelli looked at the safety of black cohosh and concluded that most case studies and case series of adverse events do not strongly show a causal link to black cohosh[4]. However, in two case reports of hepatotoxicity, black cohosh cannot be ruled out at a potential cause. Adverse events in clinical trials have been shown to be no different than placebo. The most recent research has suggested that black cohosh does not have estrogenic effects, or may be a SERM[3]. Some research has demonstrated an in vitro anti-tumor effect[4] and at least two RCTs have studied black cohosh in breast cancer survivors (although those with metastatic disease were excluded)[4,5]. In the trials some patients were taking tamoxifen or aromatase inhibitors concomitantly.
Since the evidence does not support the efficacy of black cohosh for vasomotor symptoms, it is not the first choice for most patients. However, since it has a low side effect profile and the placebo effect has been shown to be very large in many menopause trials, black cohosh could be acceptable for women looking for something, having failed or with contraindications to phytoestrogens/red clover or hormone therapy. Because of its lack of estrogenic effects, it can be considered as a first line therapy in women with a history of non-metastatic breast cancer.
References:
1Leach MJ, Moore V. Black cohosh (Cimicifuga spp.) for menopausal symptoms. Cochrane Database of Syst Rev. 2012;9:CD007244.
2Borrelli F, Ernst E. Black cohosh (Cimicifuga spp.) for menopausal symptoms: a systematic review of its efficacy. Pharmacological Research 2008;58:8-14.
3Barrette E. et al. Black cohosh (Cimicifuga racemosa [L.] Nutt.). Natural Standard. 2013. http://www.naturalstandard.com/databases/sports/all/blackcohosh.asp? Accessed March 7, 2013.
4Borrelli F, Ernst E. Black cohosh (Cimicifuga spp.) for menopausal symptoms: a systematic review of adverse events. Am J of Obs and Gyn. 2008;199:455-66.
5Pockaj BA, Gallagher JG, Loprinzi CL, Stella PJ, Barton DL, Sloan JA, et al. Phase III double-blind, randomized, placebo-controlled crossover trial of black cohosh in the management of hot flashes: NCCTG Trial N01CC1. Journal of Clin Onc. 2006;24:2836–41.
6Leach MJ, Moore V. Black cohosh (Cimicifuga spp.) for menopausal symptoms. Cochrane Database of Syst Rev. 2012;9:CD007244.
A second 2008 systematic review by Borrelli looked at the safety of black cohosh and concluded that most case studies and case series of adverse events do not strongly show a causal link to black cohosh[4]. However, in two case reports of hepatotoxicity, black cohosh cannot be ruled out at a potential cause. Adverse events in clinical trials have been shown to be no different than placebo. The most recent research has suggested that black cohosh does not have estrogenic effects, or may be a SERM[3]. Some research has demonstrated an in vitro anti-tumor effect[4] and at least two RCTs have studied black cohosh in breast cancer survivors (although those with metastatic disease were excluded)[4,5]. In the trials some patients were taking tamoxifen or aromatase inhibitors concomitantly.
Since the evidence does not support the efficacy of black cohosh for vasomotor symptoms, it is not the first choice for most patients. However, since it has a low side effect profile and the placebo effect has been shown to be very large in many menopause trials, black cohosh could be acceptable for women looking for something, having failed or with contraindications to phytoestrogens/red clover or hormone therapy. Because of its lack of estrogenic effects, it can be considered as a first line therapy in women with a history of non-metastatic breast cancer.
References:
1Leach MJ, Moore V. Black cohosh (Cimicifuga spp.) for menopausal symptoms. Cochrane Database of Syst Rev. 2012;9:CD007244.
2Borrelli F, Ernst E. Black cohosh (Cimicifuga spp.) for menopausal symptoms: a systematic review of its efficacy. Pharmacological Research 2008;58:8-14.
3Barrette E. et al. Black cohosh (Cimicifuga racemosa [L.] Nutt.). Natural Standard. 2013. http://www.naturalstandard.com/databases/sports/all/blackcohosh.asp? Accessed March 7, 2013.
4Borrelli F, Ernst E. Black cohosh (Cimicifuga spp.) for menopausal symptoms: a systematic review of adverse events. Am J of Obs and Gyn. 2008;199:455-66.
5Pockaj BA, Gallagher JG, Loprinzi CL, Stella PJ, Barton DL, Sloan JA, et al. Phase III double-blind, randomized, placebo-controlled crossover trial of black cohosh in the management of hot flashes: NCCTG Trial N01CC1. Journal of Clin Onc. 2006;24:2836–41.
6Leach MJ, Moore V. Black cohosh (Cimicifuga spp.) for menopausal symptoms. Cochrane Database of Syst Rev. 2012;9:CD007244.