Black Cohosh (Actaea racemosa L [formerly Cimicifuga racemosa])
Side
effects:
mild gastric symptoms most commonly, with vomiting, and/or dizziness at
higher doses.(35) Headaches, weight gain,(37) breathlessness, malaise,
rash, hot flushes rarely reported as well.(16)
Adverse events: seven cases of liver
toxicity have been reported in Australia including liver failure requiring
transplant.(38) It is not possible to ascribe the liver toxicity to black
cohosh as most of the patients were taking multi-herb preparations at
the time of developing symptoms,(39) though one case was associated with
Remifemin plus other medications.(16) In most of the Australian cases,
no assay of the herbal preparation was performed to exclude contaminants
as a cause (39) and other etiologies of liver disease were not definitively
ruled out. (40) In the UK, black cohosh has possibly been associated with
thrombosis, bradycardia, and hypertension, though again, causality is
unclear.(16) One case of seizures was reported in a 34 year old woman
taking black cohosh for unknown reasons.(16) In another case, an infant
whose mother had taken unknown quantities of black and blue cohosh at
42 weeks developed seizures and respiratory distress.(3) Teratogenicity,
mutagenicity, and carcinogenicity studies are reportedly negative.(3)
Precautions/contraindications: Not
recommended for pregnant or nursing women or for children, due to lack
of safety data in these groups.(3,4)
Interactions with disease states: Persons with known liver disease should probably avoid black cohosh (see adverse events). Physicians should use caution in patients with breast cancer. Studies have shown conflicting results, with one trial suggesting that black cohosh increases the incidence of breast cancer metastasis in the MMTV-neu mouse model, but no increase in primary tumor incidence.(3)