More than two centuries ago, Native Americans discovered that the root of the black cohosh plant (Cimicifuga racemosa) helped relieve menstrual cramps, and symptoms of menopause including hot flashes, irritability, mood swings, and sleep disturbances. Today, the roots of black cohosh are still often used for these purposes. In fact, the herb has been widely used for more than 40 years in Europe and is approved in Germany for premenstrual discomfort, painful menstruation, and menopausal symptoms.
A dozen studies or more conducted throughout the 1980s and 1990s confirm that the long-standing use of black cohosh for menopausal symptoms has scientific validity. For example, in a German study involving 629 women, black cohosh improved physical and psychological menopausal symptoms in more than 80% of the participants within four weeks. In a second study, 60 menopausal women were given black cohosh extract, conjugated estrogens, or diazepam (a leading anti-anxiety medication) for three months. Those who received black cohosh reported feeling significantly less depressed and anxious than those who received either estrogens or diazepam. In another study, 80 menopausal women were treated for 12 weeks with black cohosh extract, conjugated estrogens, or placebo. Black cohosh improved anxiety, menopause and vaginal symptoms. In addition, the number of hot flashes dropped from 5 to less than 1 average daily occurences in the black cohosh group compared to those taking estrogen in whom hot flashes dropped from 5 to 3.5 daily occurences.
Given these examples, and results of other studies, some experts have concluded that black cohosh may be a safe and effective alternative to estrogen replacement therapy (ERT) for women who cannot or will not take ERT for menopause.
The American College of Obstetricians and Gynecologists (ACOG) reports, however, that many of these studies were poorly designed and did not evaluate the safety and effectiveness of black cohosh beyond 6 months of use. Despite this limited evidence, the ACOG still recognizes the value of black cohosh for menopausal symptoms. Until further studies are conducted, however, the ACOG recommends only short-term (less than 6 months) use of this herb for the relief of hot flashes specifically.
Hot Flashes with treatment for Breast Cancer
Many breast cancer patients use black cohosh to ease hot flashes, a common side effect of medications used to treat breast cancer such as tamoxifen. While black cohosh may reduce the number and intensity of hot flashes in breast cancer patients, two well-designed studies recently concluded that the herb is no more effective than placebo.
In addition, although there is some debate about this, black cohosh may contain plant based estrogens, called phytoestrogens. Therefore, there is some concern that if there are phytoestrogens in black cohosh, they may stimulate the growth of breast tumors. This idea has not been substantiated scientifically; in fact, some studies suggest that black cohosh may inhibit the growth of breast cancer cells in test tubes. Additional research is needed before conclusions can be drawn about use of black cohosh in women with a history of or risk for developing breast cancer (such as strong family history).
Preliminary studies also suggest that black cohosh may help reduce inflammation associated osteoarthritis and rheumatoid arthritis. In a review of scientific studies, researchers concluded that a combination of black cohosh, willow bark (Salix spp.), sarsaparilla (Smilax spp.), guaiacum (Guaiacum officinale) resin, and poplar bark (Populus tremuloides) may help relieve symptoms of osteoarthritis.
Some experts suggest that the plant based estrogens in black cohosh, in theory, could help prevent osteoporosis. This theory has yet to be tested scientifically.
Black cohosh is a tall, flowering plant found in rich, shady woods in eastern areas of North America. A member of the buttercup family, black cohosh is also known as black snakeroot, bugbane, bugwort, and squawroot. Its rhizomes and roots (both underground parts of the plant) are used for medicinal purposes.
What's It Made Of?
Black cohosh contains glycosides (sugar compounds), isoferulic acids (substances with anti-inflammatory effects), and, possibly, phytoestrogens (plant based estrogens), among several other active substances.
Black cohosh is available in capsules, tablets, liquid tincture that can be mixed in water, and dried root that can be simmered in water.
Black cohosh should not be confused with blue cohosh, an herb that is reported to have similar effects, but has not been thoroughly tested for its safety and effectiveness and may actually behave like nicotine.
How to Take It
There are no known scientific reports on the pediatric use of black cohosh. Therefore, it is not currently recommended for children.
The recommended dose of black cohosh ranges from 40 to 80 mg per day. For black cohosh tincture, that equals 2 to 4 mL, three times per day in water or tea. Capsules or tablets may be preferred; two will likely provide the recommended daily dose.
To make a black cohosh drink, put 20 g of dried root in 34 oz of water. Bring to a boil and then simmer 20 to 30 minutes until the liquid is reduced by a third. Strain, cover, and store in the refrigerator or a cool, dry place. The liquid keeps for up to 48 hours. Drink one cup three times daily.
The use of herbs is a time-honored approach to strengthening the body and treating disease. Herbs, however, contain active substances that can trigger side effects and that can interact with other herbs, supplements, or medications. For these reasons, herbs should be taken with care, under the supervision of a practitioner knowledgeable in the field of botanical medicine.
Some individuals taking high doses of black cohosh have reported side effects including abdominal pain, diarrhea, dizziness, headaches, joint pains, nausea, slow heart rate, tremors, visual dimness, and vomiting.
It is not clear at this point whether black cohosh stimulates the growth of breast cancer cells or inhibits their growth; research to date has been limited and has produced mixed results. Women with a history of breast cancer, therefore, and those at a high risk for developing breast cancer (for example, a strong family history like a mother or sister with breast cancer) should not take black cohosh without talking to a healthcare provider.
Pregnant and breastfeeding women should avoid black cohosh as the herb may stimulate contractions and lead to premature labor.
There are no known scientific reports of interactions between black cohosh and conventional medications.
Blumenthal M, Busse WR, Goldberg A, et al. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Boston, Mass: Integrative Medicine Communications; 19998:90.
Blumenthal M, Goldberg A, Brinkmann J, eds. Herbal Medicine: Expanded Commission E Monographs. Newton, Mass: Integrative Medicine Communications; 2000:22-26.
Dixon-Shanies D, Shaikh N. Growth inhibition of human breast cancer cells by herbs and phytoestrogens. Oncol Rep. 1996;6(6):1383-1387.
Ernst E, Chrubasik S. Phytoanti-inflammatories. A systematic review of randomized, placebo-controlled, double-blind trials. Rheum Dis Clin North Am. 2000;26(1):13-27.
Foster S. Black Cohosh: Cimicifuga racemosa. A literature review. HerbalGram. 1999;45:37-49.
Foster S, Tyler V. Tyler's Honest Herbal. Binghamton, NY: The Haworth Herbal Press; 2000.
Guillaume G. Postmenopausal osteoporosis and Chinese medicine. Am J Acupuncture. 1992;20(2):105-111.
Jacobson JS, Troxel AB, Evans J, et al. Randomized trial of black cohosh for the treatment of hot flashes among women with a history of breast cancer. J Clin Oncol. 2001;19(10):2739-2745.
Lieberman S. A review of the effectiveness of Cimicifuga racemosa (black cohosh) for the symptoms of menopause. J Womens Health. 1998;5:525529.
Liske E. Therapeutic efficacy and safety of Cimicifuga racemosa for gynecologic disorders. Advances in Natural Therapy. 1998;75:45-53.
McFarlin BL, Gibson MH, O'Rear J, et al. A national survey of herbal preparation use by nurse-midwives for labor stimulation. Review of the literature and recommendations for practice. J Nurse Midwifery. 1999;44(3):205216.
McKenna DJ, Jones K, Humphrey S, Hughes K. Black cohosh: efficacy, safety, and use in clinical and preclinical applications. [Review]. Altern Ther Health Med. 2001;7(3):93-100.
Pepping J. Alternative therapies: black cohosh: Cimicifuga racemosa. Am J Health-Syst Pharm. 1999;56:1400-1402.
Rotblatt M, Ziment I. Evidence-based herbal medicine. Philadelphia, PA: Hanley & Belfus, Inc.;2002:98-103.
Schulz V, Hänsel R, Tyler VE. Rational Phytotherapy. Berlin, Germany: Springer-Verlag; 1998.
Taylor M. Alternatives to Hormone Replacement Therapy. Comprehensive Therapy. 1997;23:514532.
Thacker HL, Booher DL. Management of perimenopause: focus on alternative therapies. Cleveland Clin J Med. 1999;66(40):213218.
Wade C, Kronenberg F, Kelly A, Murphy PA. Hormone-modulating herbs: implications for women's health. J Am Med Womens Assoc. 1999;54(4):181-183.
Review Date: April 2002 Reviewed By: Participants in the review process include: Constance Grauds (April 1999), RPh, President, Association of Natural Medicine Pharmacists, San Rafael, CA; Jacqueline A. Hart, MD, Department of Internal Medicine, Newton-Wellesley Hospital, Harvard University and Senior Medical Editor Integrative Medicine, Boston, MA; Gary Kracoff, RPh (Pediatric Dosing section February 2001), Johnson Drugs, Natick, MA; Steven Ottariono, RPh (Pediatric Dosing section February 2001), Veteran's Administrative Hospital, Londonderry, NH; R. Lynn Shumake, PD, Director, Alternative Medicine Apothecary, Blue Mountain Apothecary & Healing Arts, University of Maryland Medical Center, Glenwood, MD; Tom Wolfe, P.AHG (April 1999), Smile Herb Shop, College Park, MD. All interaction sections have also been reviewed by a team of experts including Joseph Lamb, MD (July 2000), The Integrative Medicine Works, Alexandria, VA;Enrico Liva, ND, RPh (August 2000), Vital Nutrients, Middletown, CT; Brian T Sanderoff, PD, BS in Pharmacy (March 2000), Clinical Assistant Professor, University of Maryland School of Pharmacy; President, Your Prescription for Health, Owings Mills, MD; Ira Zunin, MD, MPH, MBA (July 2000), President and Chairman, Hawaii State Consortium for Integrative Medicine, Honolulu, HI.
The publisher does not accept any responsibility for the accuracy of the information or the consequences arising from the application, use, or misuse of any of the information contained herein, including any injury and/or damage to any person or property as a matter of product liability, negligence, or otherwise. No warranty, expressed or implied, is made in regard to the contents of this material. No claims or endorsements are made for any drugs or compounds currently marketed or in investigative use. This material is not intended as a guide to self-medication. The reader is advised to discuss the information provided here with a doctor, pharmacist, nurse, or other authorized healthcare practitioner and to check product information (including package inserts) regarding dosage, precautions, warnings, interactions, and contraindications before administering any drug, herb, or supplement discussed herein.