Black Cohosh Root Information and Side Effects

Black Cohosh Root Information and Side Effects

Black Cohosh, a North American forest plant traditionally used to treat snake bites, is also known as Black Snakeroot. It is used often to provide support for menopausal hot flashes. Black Cohosh stimulates estrogen-like activity in the body. Women undergoing estrogen replacement therapy should consult their doctors prior to supplementing with Black Cohosh.

Historical Uses of Black Cohosh

North American Indians used this medicinal plant for gynecological disorders, kidney disorders, malaria, malaise, rheumatism, and sore throat. Additionally, it was used for backache, colds, constipation cough, hives, and to induce lactation. Black cohosh served as a home remedy in the 19th century for fever and rheumatism, as a diuretic, and to induce menstruation. Its popularity was strong among a group of alternative practitioners who referred to black cohosh as macrotys and prescribed it for lung conditions, neurological conditions, rheumatism, and conditions pertaining to women's reproductive organs such as infertility, menstrual problems, inflammation of the uterus or ovaries, potential miscarriage, and relief of labor pains. There is no scientific evidence to support the usage of Black Cohosh for any of these conditions.

How it Works

The active constituents in black cohosh, that are reported to provide its medicinal value, include triterpene glycosides (e.g. acetin and deoxyactein) and isoflavones. Additional ingredients that may lend to its medicinal value include aromatic acids, resins, fatty acids, tannins, starches and sugars.

As a woman reaches menopause estrogen production decreases while luteinizing hormone (LH) secretions increase. The result often is intense hot flashed. Studies suggest that black cohosh has some estrogen regulating ability and may also decrease LH secretions whereby dampening the severity of hot flashes associated with menopause. More studies are needed.

Dosage and Administration

Black Cohosh can be taken in the form of the fresh or dried root, or as a liquid extract. It is also available commercially in capsule and tablet form. Black Cohosh is taken orally. The usual daily dosage is 40 milligrams, but because the strength of commercial preparations may vary, be sure to follow the manufacturer's instructions whenever available.

Black Cohosh Side Effects

Breast-feeding or pregnant women should not take black cohosh. Large amounts (over several grams daily) of black cohosh can cause abdominal pain, dizziness, headaches, and nausea. Black cohosh should not serve as an alternate for hormone replacement therapy during menopause.

Additionally, women with breast cancer may want to abstain from black cohosh until its impact on breast tissue is understood.


Although no reported negative interactions with other drugs exist, black cohosh has not been studied thoroughly.

Supporting Literature

Jarry H, Harnischfeger G, D√ľker E. Studies on endocrine effects of the contents of Cimicifuga racemosa. 2. In vitro binding of compounds to estrogen receptors. Planta Medica 1985;51:46-49, 316-319.
Foster S. Herbs for Your Health. Loveland, CO: Interweave Press, 1996, 12-13.
Murray MT. The Healing Power of Herbs. Rocklin, CA: Prima Publishing, 1995, 376.