Black Cohosh: Uses, Benefits, Dosage & Safety
Last updated: June 2026 · Reviewed by the FactoWiki Editorial Team for clarity and source accuracy
Quick summary
Black cohosh is one of the most-used herbs for menopausal hot flushes. Evidence is mixed, and rare liver-safety reports mean it is not risk-free.
What is Black Cohosh?
Black cohosh (Actaea racemosa) is a North American woodland plant whose root has long been used for women's health, especially menopausal symptoms.
What Black Cohosh is commonly used for
In supplements, Black Cohosh is most often included for women's hormone & thyroid support. It is used as nutritional support, not as a treatment for any medical condition — the distinction matters, because the claims on a sales page are often stronger than the evidence allows.
How Black Cohosh works
Its mechanism is unclear; despite early assumptions it does not appear to act mainly as an oestrogen, and may instead influence serotonin or other pathways involved in temperature regulation.
What the evidence says
Here's an honest snapshot of what published research suggests about Black Cohosh — including where the evidence is limited.
- Black cohosh has many trials for menopausal hot flushes with inconsistent results — some positive, some no better than placebo. It is among the better-studied options but far from definitively effective.
- Study quality and doses vary, and a result seen in research doesn't guarantee the same for any individual — use the sources below to check the current evidence on Black Cohosh rather than relying on marketing claims.
Typical dosage used in studies
Studies commonly use standardised extracts equivalent to about 20–40 mg of root twice daily, taken for several weeks to months. This is general information from research, not a personal recommendation or a dosing instruction.
Side effects and safety
Black cohosh is usually well tolerated but has rare reports of liver injury, so it should be stopped if symptoms of liver problems occur. It is generally avoided in pregnancy and in liver disease. As with any supplement, it's sensible to introduce Black Cohosh on its own, use a trusted brand, and stop if you notice any reaction.
Medication interactions and who should avoid Black Cohosh
Medication & safety check
Herbs interact with prescription medicines more often than people expect — affecting drug levels, bleeding, blood pressure, blood sugar or sedation — and Black Cohosh is no exception. If you take any regular medication, are pregnant or breastfeeding, or manage a health condition, confirm Black Cohosh is appropriate for you before starting.
This is general information, not personal medical advice. If you take any medication, are pregnant or breastfeeding, or have a health condition, confirm it's safe to use Black Cohosh with your doctor or pharmacist first.
Sources & further reading
For authoritative background and the current research base on Black Cohosh, consult:
- PubMed — search the research on Black Cohosh
- NCCIH — Herbs at a Glance
- MedlinePlus — herbs & supplements
- MedlinePlus — drugs, herbs & supplements
Frequently asked questions
Does Black Cohosh actually work?
Black cohosh has many trials for menopausal hot flushes with inconsistent results — some positive, some no better than placebo. It is among the better-studied options but far from definitively effective. As with most supplements, results vary between people and the marketing is often stronger than the evidence — so it's worth checking the research before relying on it.
Is Black Cohosh safe to take?
For most healthy adults at normal doses it's generally well tolerated, but there are real cautions. Black cohosh is usually well tolerated but has rare reports of liver injury, so it should be stopped if symptoms of liver problems occur. It is generally avoided in pregnancy and in liver disease. If you take medication, are pregnant or breastfeeding, or have a health condition, check with a doctor or pharmacist first.
What is Black Cohosh used for?
In supplements, Black Cohosh is mainly included for women's hormone & thyroid support — as nutritional support, not as a treatment for any medical condition.
Where you'll find Black Cohosh
On FactoWiki, Black Cohosh is the kind of ingredient you'll see discussed in these supplement categories. Each category guide breaks down what the evidence does and doesn't support.
Related ingredients to explore
Ingredients often studied or formulated alongside Black Cohosh — useful for understanding the full picture of a formula.