Muscle damage induced by black cohosh (Cimicifuga racemosa)

Extracts of black cohosh (Cimicifuga racemosa) are commonly used for the treatment of symptoms associated with menopause. Adverse events with black cohosh are rare, mild and reversible. A few number of serious adverse events, including hepatic and circulatory conditions, have been also reported, but without a clear causality relationship. We report the case of a woman with severe asthenia, and very high blood levels of creatine phosphokinase and lactate dehydrogenase. The patient referred to take a dietary supplement derived from black cohosh for ameliorating menopause vasomotor symptoms. To exclude a possible involvement of this product, the patient was suggested to discontinue this therapy. After suspicion the patient showed a progressive normalization of biochemical parameters and improvement of clinical symptoms. We can hypothesise a causative role for black cohosh in the muscle damage observed in this patient. Factors suggesting an association between black cohosh and the observed myopathy included the temporal relationship between use of herbal product and asthenia and the absence of other identified causative factors. Rechallenge with the suspected agent was inadvisable for ethic reasons because of the risk of a serious relapse. This is the first time that asthenia associated with high muscle enzymes serum levels by black cohosh has been reported. In our opinion, this report is of interest because of the widespread diffusion of use of black cohosh as an alternative medicine for relief from menopausal symptoms.