Is Black Cohosh Safe?
Posted On April 11, 2008
Black Cohosh has been used for centuries to reduce menopausal symptoms and to bring on a slow labour in the late stages of pregnancy. Preparations of this herb are commonly sold in European pharmacies to relieve hot flashes.
Traditionally warnings for this herb have included cautions that it will bring on early contractions so should not be used early in pregnancy and only in very small doses later and adverse effects on blood pressure.
More recently, black cohosh has been linked to reports of liver damage. In May 2007 the Therapeutic Goods Administration (TGA) updated its labelling rules for products containing black cohosh. Preparations containing this herb must be labelled with a cautionary advice of possible risk of liver damage.
The TGA’s expert advisory found that “…..Black cohosh is still suitable for use in complementary medicines, but recommended that the current warning statement on the medicine label be revised to better inform consumers about the risk and also to provide sufficient information to assist in the early detection of liver damage and, if detected, to seek medical attention.”
Yesterday I can across this article in The Medical Journal of Australia – “Liver failure associated with the use of black cohosh for menopausal symptoms”. By the sound of it the authors of this article are reporting on the same Australian cases of liver failure that had already been investigated by the TGA, but it does provide more information on the individual (9th) case.
It is an interesting read…..particularly the “….Two safety reviews have found black cohosh extract to be well tolerated and adverse events to be rare when it is taken for up to 6 months. However, the seven case reports of hepatotoxicity potentially associated with black cohosh use in the past decade raise concern. Currently, there is no known biologically plausible mechanism to explain this hepatotoxicity, which is likely to be multifactorial.” I find their statement of“The most likely cause of our patient’s liver failure was her use of black cohosh,…” to be quite a leap although they do point out that she did not take the preparation according to instructions and exceeded the recommended duration of treatment by taking black cohosh for 3 years instead of the recommended 2 months.
I am no expert and I am certainly no scientist. The occurrence of liver damage in women who take black cohosh is very scary stuff. The TGA has this to say “… At the time of the review, there were 47 cases of liver reactions worldwide, including 9 Australian cases. In Australia, four patients were hospitalised, including two who required liver transplantation. Although some reports are confounded by multiple ingredients, by more than one medication or by other medical conditions, there is sufficient evidence of a causal association between Black cohosh and serious hepatitis. Considering the widespread use of black cohosh, the incidence of liver reaction appears to be very low. “
Here is my personal recommendation to all my readers who may be thinking of using black cohosh:
Black Cohosh has been used effectively for centuries – but that doesn’t mean that it may not also have some side effects. Before you take this herb, check with a professional herbalist, and if you have any liver problems (or have a family history of liver problems) I would find an alternative herb to treat my menopausal symptoms with.