Researchers from Johann Wolfgang Goethe University of Frankfurt/Main, in Hanau, Germany, reviewed the evidence and believe the risk is less than suspected.

First, the details.

• 69 reports of liver disease suspected to be caused by black cohosh (aka Actaea racemosa and Cimicifuga racemosa) were reviewed and analyzed.
• The sources of the reports were 11 published case reports and 58 spontaneous reports to national regulatory agencies.

And, the results.

• Re-evaluation raised serious doubts about the ability of black cohosh to cause liver disease.
• The reports that served as the sources of the reaction were of poor quality.
• There were major inconsistencies for the same patient regarding reported data.
• All cases had confounding variables such as…
  • Quality of reported data
  • Uncertainty of the black cohosh product, quality, and identification
  • Undisclosed indication for it’s use
  • Insufficient adverse event definition
  • Lack of temporal association and dechallenge (did the reaction resolve when black cohosh was discontinued?)
  • Missing or inadequate evaluation of alcohol use or the presence of other drugs and diseases
  • Failure to re-exposure test to black cohosh, and alternative cause of the patient’s condition

The bottom line?

The authors concluded, “The presented data do not support the concept of hepatotoxicity in a primarily suspected causal relationship to the use of black cohosh.”

In other words, conclusive proof of a cause and effect relationship between black cohosh and liver toxicity is not available.

“Nonetheless,” MayoClinic.com advises, “Patients with liver disease should consult a licensed healthcare professional before using black cohosh.”

4/17/10 20:15 JR