| PDF (Download) | Black cohosh (Cimicifuga racemosa) | | Date: March 15, 2004 | HC# 090432-252 |
Re: Brief Review of Clinical Indications of Black Cohosh
Monograph. Cimicifuga racemosa Alternative Medicine Review. 2003;8(2):186-189.
Black cohosh (Cimicifuga racemosa or Actaea racemosa), also known as black snakeroot, black root, bugbane, rattle root, rattle top, rattle squawroot, snake root or rattle weed, was used for many gynecological conditions 'by Native Americans and Europeans...predating settlement of the New World' (presumably European settlement). It was used by mid-nineteenth century eclectic physicians for 'women's problems' ranging from endometritis to severe pain following child birth. It has been prescribed for rheumatism and nervous disorders as well. Black cohosh has also become an increasingly popular remedy for menopausal symptoms, especially with the growing awareness of the risks of conventional hormone replacement therapy.
The constituents of black cohosh have not been thoroughly characterized, which contributes to a lack of clarity concerning its mechanisms of action and a debate among scientists and practitioners as to whether it exerts an estrogenic effect or whether it actually contains phytoestrogen(s). Chemical study results are contradictory. While phytoestrogens are generally believed to be milder than human estrogen, there is some concern that they might increase the risk for estrogen-dependent cancers. An estrogenic isoflavone, formononetin, has been reported as a constituent of black cohosh, but was not detected in alcohol extracts of the root and rhizome. Other black cohosh effects may depend upon the type of extract or preparation used. Resinous constituents soluble in alcohol have been used to improve circulation and reduce blood pressure by dilating blood vessels. Black cohosh roots also contain triterpenoids, cimicifugoside, and cinnamic acid derivatives.
The monograph examines results of clinical trials and potential clinical indications involving conditions such as menopause, where the herb 'appear[s] to be a safe and effective alternative to estrogen therapy'; menstrual migraine, which affects approximately 30% of menstruating women; breast cancer, where in vitro studies have found an estrogen-antagonistic effect of black cohosh extract on human breast cancer cells; and tinnitus. The rhizome has been shown to have anti-inflammatory, analgesic, and antipyretic effects.
No studies have documented drug interactions with black cohosh, although it may potentiate tamixofen. It has been found to potentiate antihypertensive medications in rabbits, but not in dogs or humans. It is generally well tolerated, with only mild gastrointestinal side effects reported at recommended doses. Some trials have reported similar results for extracts standardized to contain 1 mg of triterpines per 20 mg of extract, whether 40 or 80 mg was used daily. It is suggested that black cohosh be avoided during pregnancy, due to possible uterine-stimulating effects, and during lactation, as it may cause colic in the nursing child.
-Mariann Garner-Wizard |