Review & meta-analysis: isopropanolic black cohosh extract iCR for menopausal symptoms–an update on the evidence

Abstract

A systematic literature search revealed 35 clinical studies and one meta-analysis comprising 43,759 women, of which 13,096 were treated with isopropanolic Cimicifuga racemosa extract (iCR). Compared to placebo, iCR was significantly superior for treating neurovegetative and psychological menopausal symptoms, with a standardized mean difference of −0.694 in favor of iCR (p < 0.0001). Effect sizes were larger when higher dosages of iCR as monotherapy or in combination with St. John’s wort (Hypericum perforatum [HP]) were given (−1.020 and −0.999, respectively), suggesting a dose-dependency. For psychological symptoms, the iCR+HP combination was superior to iCR monotherapy. Efficacy of iCR was comparable to low-dose transdermal estradiol or tibolone. Yet, due to its better tolerability, iCR had a significantly better benefit–risk profile than tibolone. Treatment with iCR/iCR+HP was well tolerated with few minor adverse events, with a frequency comparable to placebo. The clinical data did not reveal any evidence of hepatotoxicity. Hormone levels remained unchanged and estrogen-sensitive tissues (e.g. breast, endometrium) were unaffected by iCR treatment. As benefits clearly outweigh risks, iCR/iCR+HP should be recommended as an evidence-based treatment option for natural climacteric symptoms. With its good safety profile in general and at estrogen-sensitive organs, iCR as a non-hormonal herbal therapy can also be used in patients with hormone-dependent diseases who suffer from iatrogenic climacteric symptoms.