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Cimicifuga racemosa, black cohosh

Please note

From 13th September 2011, this page will not be revised. Changes to information about this plant will only appear on the Actaea racemosa page.


Though used by Native Americans to treat a wide variety of, mostly female, conditions, its use as a herbal treatment for the hot flushes of the menopause may be damaging. The stunning white flower spikes make it an attractive plant for the garden though it is best viewed at a distance because of its smell.



Meaning of the Name

From ‘cimex’, a bug, and ‘fugo’, ‘to force to flee’.  The Linnaean name for this plant derives from its reputation for being an insect repellent. This plant gives an example of the difference between Linnaeus and the Linnaean system. Linnaeus classified this plant as Actaea but it was later placed in the Cimicifuga genus. Recent gene studies have shown that Linnaeus was right all along. 
Has flowers in racemes, that is on short stems from a longer stem.

Common Names and Synonyms

black cohosh, snakeroot, black bugbane, squaw root. Sometimes called Actaea racemosa.

Cimicifuga racemosa, black cohosh

Cimicifuga racemosa, black cohosh

How Poisonous, How Harmful?

No alkaloids have been isolated but it contains a mixture of resins which have been called cimicifugin, macrotin, or macrotyn. Also, contains an oestrogenic sedative hence its use for menstrual and labour pain.

Even small doses can cause headaches and larger doses can lead to vertigo, impaired vision, pupillary dilatation, nausea, vomiting and bradycardia. Some reports suggest it can cause delirium tremens.

It is to be avoided during pregnancy as it may cause miscarriage.

New information on the possible extent of liver damage which this plant may cause has led to warnings having to be placed on labels of herbal remedies which are supposed to assist with the menopause. Following concerns about possible problems with HRT drugs, the use of black cohosh had increased significantly in the last couple of years but, anyone who believes they may be susceptible to liver damage is warned against using it.

Cimicifuga racemosa, black cohosh

Cimicifuga racemosa


There have been reports of liver damage resulting from use of black cohosh but there are those who say the evidence is weak and, in the reported cases, not enough was done to confirm that the plant extract was the cause of the hepatitis.

Folklore and Facts

Used by Native Americans to treat female complaints, rheumatic conditions and snakebites.

Used as an insect repellent.

Tea made from the roots if sprinkled around a room will prevent evil spirits from entering.

Supposed to counter the effect of rattlesnake bite.

It has an unpleasant smell which is said to keep insects at bay.

Publication, in November 2008, of research suggesting that black cohosh, taken as a herbal remedy, can result in the spread of breast cancer to the lungs resulted in a radio debate between a doctor and a herbal specialist. The herbal specialist fell back on the old line of 'it's been used for hundreds of years' but was sadly not asked to produce the reports of the double blind, placebo controlled trials of black cohosh conducted in the 17th century. Because, of course, there are no such studies and use of all herbal remedies is based on purely anecdotal evidence which can not be systematically verified.