Black cohosh

A plant native to North America, also called Actaea racemosa. It was used by Native Americans for period problems, and it is now the most purchased herbal product for menopause symptoms. How it works is not known.

• A Cochrane review of 16 studies in 2,027 women found insufficient evidence to support black cohosh for menopausal symptoms, and called for better trials.
• NICE says people can be told there is some evidence that black cohosh may relieve hot flashes and night sweats. It also says preparations vary, their safety is uncertain, and interactions with other medicines have been reported.
• The Menopause Society reviewed the evidence in 2023 and lists supplements and herbal remedies, black cohosh included, among the things it does not recommend for hot flashes.
• The NHS says there is very little evidence on how well herbal remedies like black cohosh work, or how safe they are.
• Most trials ran for 6 months or less, so nobody has tested what happens over years.

One widely studied product is standardised to the equivalent of 40mg of black cohosh root and rhizome per daily dose. Products differ from each other, so one product's dose does not read across to another.

This is what the research used. It is not a dose for you.

For menopause symptoms, black cohosh is treated as a medicine in the UK. A product sold for that use needs a traditional herbal registration, shown by the THR mark. A food supplement cannot make that claim.

In the US the rules are looser. A label may say how a nutrient supports the body if the company holds evidence for it. The FDA does not check the claim first, which is why US labels carry the line saying the FDA has not evaluated it.

• At least 83 cases of liver damage have been reported worldwide in people using black cohosh, including hepatitis, liver failure and raised liver enzymes.
• Stop and get medical help if you notice yellowing skin or eyes, dark urine, unusual tiredness or pain in the upper right of your abdomen.
• Herbal products are not regulated like medicines. What is in the bottle can differ from what is on the label.
• Interactions with other medicines have been reported, so a pharmacist should see your full list first.

• You have liver disease, or take medicines that affect the liver.
• You have had breast cancer or are at high risk of it.
• You take any prescription medicine at all.

This is general information, not medical advice. Check with your doctor or pharmacist, especially if you take medication.

• Leach and Moore, Black cohosh for menopausal symptoms, Cochrane Database of Systematic Reviews
• NIH Office of Dietary Supplements, Black cohosh fact sheet
• NICE NG23, Menopause: identification and management, recommendations
• NHS, Menopause and perimenopause treatment

Checked against these sources on 2026-09-19.