Black cohosh (Cimicifuga racemosa) is a native American plant whose roots may provide a safe alternative to synthetic hormones in treating menopause and other female reproductive symptoms. The botanical has been widely used for more than 40 years in Europe and is approved by the German Commission E for premenstrual discomfort, dysmenorrhea, and menopausal symptoms. Black cohosh is sometimes called "black snakeroot," "bugbane," "bugwort," or "squawroot."

Although physicians widely recommend hormone replacement therapy (HRT) for menopause, only 10% to 20% of menopausal women take it. Only half of patients who receive prescriptions for HRT have them filled and fewer than 40% of those who start HRT are still taking it a year later. The primary reason women avoid HRT is fear of breast cancer. While shying away from conventional hormone treatment, Americans are embracing alternative therapies. One in three uses botanicals, herbals, or other alternative treatments at some time.

In a German study involving 629 female patients, black cohosh improved physical and psychological menopausal symptoms in more than 80% of the subjects within six to eight weeks. The botanical was well tolerated, with only 7% of patients reporting mild, transient stomach upset. A double-blind study of 60 patients showed that black cohosh relieved menopausal depression and anxiety better than both conjugated estrogens and diazepam (Valium). Patients taking black cohosh also exhibited greater increases in the number of superficial cells in the vaginal lining. The number of daily hot flashes dropped from an average of five to fewer than one in the black cohosh group. The estrogen group reported a decrease from 5 to 3.5. More than 80% of the women taking black cohosh also reported improvements in tinnitus, heart palpitations, vertigo, and headaches.

Another significant benefit black cohosh offers over synthetic estrogen is that it does not stimulate the growth of estrogen-dependent, breast cancer cells. In vitro studies suggest it may actually inhibit growth of these cells.

Black cohosh relieves menopausal symptoms by suppressing the secretion of luteinizing hormone (LH) and lessening its ability to bind with receptors in the hypothalamus. Sudden bursts of LH cause hot flashes, heart palpitations, headaches, and thinning of the vaginal lining. Unlike synthetic estrogens, it does not affect follicle-stimulating hormone or prolactin release.

Although most studies have focused on black cohosh's effect on symptoms of menopause, it is also used to treat other ailments including arthritic inflammation, mild hypertension, respiratory congestion, rheumatoid arthritis, sciatica, osteoarthritis, tinnitus, muscular and neurological pain, and nervous conditions.

Black cohosh is a member of the buttercup family. It is a hardy perennial that grows in the shady woodlands of the United States and Canada. It grows up to five feet tall, and has a stout black rhizome and straight, dark brown roots. Small white flowers sprout from long, feathery racemes in June and July. The rhizome and roots are harvested in the fall.

• Roots
• Rhizome

Cimicifugin (macrotin) and isoflavone formononetin. Triterpene glycosides (principally the xylosides actein, cimicifugoside, and 27-deoxyacteine) also are present in black cohosh. Other constituents are aromatic acids (including ferulic, isoferulic, and salicylic acids), tannins, resin, fatty acids, sugars, and starch.

The unrefined dried roots and rhizome of black cohosh are odorless and have a bitter, acrid taste. Black cohosh is available over the counter in drugstores and health-food stores in several forms. The most familiar are capsules and tablets. The botanical also is available as a liquid tincture that can be mixed in water and as a dried root that's simmered in water to make a drink similar to tea. Several natural menopause treatments are made from a combination of black cohosh and other botanicals.

Black cohosh was traditionally used as an emmenagogue, antispasmodic, ulcerative (blood purifier), sedative, and nervine tonic. Clinical applications include the following.

• Relieves symptoms of premenstrual syndrome and painful menstruation
• Diminishes physical effects of menopause including hot flashes, heart palpitations, tinnitus, vertigo, and headaches. Tinnitus may respond best to a combination of black cohosh and the botanical Ginkgo biloba.
• Eases menopause's psychological effects including depression, nervousness, and irritability
• Increases the number of superficial cells in the vaginal lining, which diminishes dryness and discomfort
• Reduces inflammation associated with arthritis and rheumatism
• Slightly lowers arterial blood pressure by decreasing constriction of peripheral blood vessels
• Acts as an expectorant by increasing blood flow to the lungs and thinning respiratory mucus

It is unknown whether black cohosh mimics synthetic estrogen's tendency to lessen the risk of osteoporosis and heart disease.

Black cohosh's estrogenic activity is associated with cimicifugin (macrotin) and the isoflavone formononetin. The botanical's antihypertensive effect is associated with actein. Ferulic and isoferulic acids give black cohosh its anti-inflammatory properties.

The recommended dose is 40 mg per day of the crude drug. The following doses should be taken tid.

• Powdered root or as tea: 1 to 2 g
• Fluidextract (1:1): 4 ml (1 tsp)
• Solid (dry powdered) extract (4:1): 250 to 500 ml

For commercially available products containing black cohosh (some may be standardized to 1 mg of 27-deoxyacteine per tablet), follow the dosing instructions on the product labeling. The German Commission E had recommended administration be limited to six months. The recommendation was made before recent toxicology studies on rats, which suggest black cohosh is safe for long-term use. The U.S. FDA regulates black cohosh as a dietary supplement, providing no guidelines for dosage or duration.

• Rats given approximately nine times the therapeutic daily dose of 2 mg of 27-deoxyacteine for six months displayed no teratogenic, mutagenic, or carcinogenic effects.
• Mild gastrointestinal symptoms are the most common side effects. They include nausea, vomiting, diarrhea, and abdominal pain. Other side effects include dizziness, visual dimness, headaches, tremors, joint pain, and bradycardia.
• Although the six-month rat study attempted to replicate long-term human effects, long-term human studies have not been done.

Black cohosh is contraindicated in pregnancy, particularly during the first two trimesters because overdose may lead to premature birth. However, the botanical is often used late in pregnancy to stimulate labor. No data is available to support the use of black cohosh in women who are breastfeeding. The Germany Commission E lists no contraindications in the use of black cohosh. The botanical is appropriate for patients not suited for HRT including those with a history of breast cancer, unexplained uterine bleeding, liver and gallbladder disease, pancreatitis, endometriosis, uterine fibroids, and fibrocystic breast disease. Do not confuse black cohosh with blue cohosh, a botanical with similar properties, but less data on safety and efficacy.

Although black cohosh reportedly possesses estrogenic properties, no clinically significant interactions between black cohosh and conventional medications (including hormone replacement therapies) are known to have been reported in the literature to date, including the German Commission E monograph (Blumenthal 1998).

Black cohosh has been approved by the German Commission E for the treatment of prementrual discomfort, dysmenorrhea, and menopause discomforts.

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