Saturday Quack – Black Cohosh Can Cause Liver Problems

The benefits of black cohosh for treating menopausal symptoms are questionable. And now there’s a warning of liver failure attributed to black cohosh use. The Medical Journal of Australia published a report of this case, together with a summary of what is known about the toxicity of the herbal supplement.

A 51-year-old woman, who had gastric bypass surgery for obesity, had been taking 20 mg daily of black cohosh on-and-off for 3 years. Initial tests 2 months after the onset of symptoms indicated acute hepatitis; 6 weeks later a biopsy showed massive necrosis of liver cells, and she was listed urgently for a liver transplant. Five days later she received a liver, and has subsequently made a good recovery.

Two safety reviews have determined that black cohosh extract is well tolerated and there are only rare side effects when it’s given for up to 6 months. However, 7 cases of hepatotoxicity have been reported in the last decade. It seems likely that the herbal supplement was the cause of liver failure in the patient described above. Women taking of black cohosh should be aware of the possible risks of prolonged use, and watch for possible hepatotoxicity symptoms – jaundice, dark urine, nausea, vomiting, lethargy, and loss of appetite. And if it’s not working, don’t take it!