Black Cohosh

How does Black Cohosh work?

Black cohosh seems to have effects like the hormone estrogen, but it is not known exactly how it works.

Are there safety concerns?

Black cohosh seems to be safe for most people. It might cause some mild side effects such as stomach upset, cramping, headache, rash, a feeling of heaviness, vaginal spotting or bleeding, and weight gain.

Some reports have linked black cohosh to liver damage. It is not known for sure if black cohosh is the cause of liver damage in these cases. More information is needed. Until more is known, people who take black cohosh should watch for symptoms of liver damage such as yellowing of the skin and eyes (jaundice), unusual fatigue, or dark urine. If these symptoms develop, black cohosh should be stopped and medical attention should be sought. People who take black cohosh should get periodic blood tests to check for liver damage.

Do not use black cohosh if:

• You are pregnant or breast-feeding.
• You have breast cancer.
• You have uterine cancer.
• You have ovarian cancer.
• You have a condition called "endometriosis."
• You have uterine "fibroids."
• You have liver disease.
• You have received a kidney transplant.
• You have a condition called protein S deficiency.