Black cohosh with side effects

Herbal agent is suspected to attenuate the entire central nervous system

03/10/2014

Herbal remedies from natural medicine are often much gentler on the body than prescription drugs. However, it seems to be different with black cohosh, which women use for menopausal symptoms such as hot flashes and restlessness. Research by pharmacologists at the Medical University of Vienna has shown that the herbal active substance has a depressant effect on the entire central nervous system. In case of overdose sedative side effects could occur.

Herbal ingredient could cause sedation
The research team led by Sophia Khom and Barbara Strommer investigated the effect of the constituents of black cohosh on the so-called GABA (A) receptors in the brain. They are involved in motor control and sleep behavior. Accordingly, the herbal remedy strengthens the action of the important messenger substance GABA (gamma-amino-butyric acid). In experiments with eggs of the African clawed frog, the effect on nine different GABAA receptor subtypes was investigated. „In the study we performed, it was particularly noticeable that the natural product showed no selectivity and influenced all examined GABA (A) receptor subtypes equally. The maximum effect was about six times more pronounced compared to established substances such as diazepam, "explains Khom, who heads the experimental studies at the University of Vienna.

Herbal ingredients partly poorly understood
„From this it can be concluded that the substance probably acts on all brain-occurring GABA (A) receptors and thereby significantly reduces the excitability of nerve cells in the entire brain“, informs the University of Vienna. „Such an effect reduces restlessness, anxiety or stress, but also leads to undesirable effects such as sedation - ie attenuation of the functions of the central nervous system -, need for sleep and the loss of control of the muscles.“ This calming effect could also contribute to the reduction of postmenopausal nervousness. However, further studies are needed to confirm this.

„We believe that these and the work just published demonstrate a possible mechanism of action of these herbal extracts, which have been widely used for many years. However, we still know too little about how long these substances remain in the human organism, how they are distributed in the organism, or whether more effective, long-lived metabolites may be formed in the body, "explains Khom.