What is Black Cohosh?
Other Names: Actea racemosa, Cimicifuga racemosa
Who is this for?
Note: Black cohosh is different from both blue cohosh and white cohosh. Blue cohosh is frequently used in combination with black cohosh, but the effects of the two products are very different. White cohosh, also called white baneberry, is poisonous. It should never be taken by mouth. Individuals who have any doubts about the origin of a cohosh product should not use it.
Because premenopausal women have fewer heart problems than men of similar ages, the female hormones estrogen and progestin were thought to protect against heart disease. Therefore, hormone replacement therapy (HRT) drugs were prescribed widely for postmenopausal women. However, two recent large clinical trials--the Women's Health Initiative (WHI) and the Heart Estrogen/progestin Replacement Study (HERS)--showed that supplemental HRT is not heart protective. In fact, it increased risks of heart disease, breast cancer, and stroke for some women.
Interest has been renewed in the use of black cohosh and other "natural" alternatives for female HRT. Although black cohosh was long thought to contain chemicals that act like estrogen in the body, results of recent clinical studies have found that it not only has little or no estrogenic activity, but that it actually blocks estrogen.
Still, black cohosh is used mostly to treat complaints such as premenstrual syndrome (PMS), hormone-related migraines, and menopausal symptoms. For many women, it is at least mildly effective in relieving bloating, breast soreness, cramps, emotional changes, swelling, and other menstrual or menopausal problems. However, in clinical studies, black cohosh generally has not relieved treatment-related symptoms such as hot flashes for women who previously had breast cancer.
Studies in animals suggest that black cohosh may also have other beneficial effects. It may help slow or prevent osteoporosis, for example. A few studies that were done in the 1960s and 1970s found black cohosh to have a blood-pressure lowering effect in laboratory animals. Black cohosh also seems to be a mild sedative, which may relieve anxiety or encourage sleep. However, few human studies have been conducted to verify these results. Currently, the Office of Dietary Supplements, a division of the U.S. National Institutes of Health, is sponsoring clinical trials to test the usefulness of black cohosh for treating several conditions.
When should I be careful taking it?
Sometimes, black cohosh is used by midwives to start labor in women about to give birth. However, it should never be used by a pregnant woman without the supervision of a trained healthcare provider because it may stimulate the uterus to contract--possibly causing a miscarriage.
Women with hormone-dependent conditions such as endometriosis, uterine fibroids, and cancers of the breast, ovaries, or uterus should not take black cohosh due to its possible hormonal effects.
Men with prostate cancer should also avoid taking black cohosh.
Case reports from Australia and Europe associate black cohosh with rare instances of hepatitis,or liver damage, which resulted in liver transplants for some of the affected individuals. Although a direct relationship has not been established, individuals who have liver disease or who drink large amounts of alcohol are advised to avoid taking black cohosh.
Not enough is known about black cohosh to recommend it for use while a woman is breastfeeding an infant.
Major Side Effects:
Large doses of black cohosh may result in:
Less Serious Side Effects
Side effects that have been reported from taking black cohosh include:
What interactions should I watch for?
Chemicals in black cohosh may block estrogen in the body. When it is taken at the same time as estrogen replacement therapy or oral contraceptives, black cohosh may interfere with the way the body uses estrogen. As a result, estrogens or oral contraceptives may not be as effective, some women may experience increased side effects, and the risk of anunintended pregnancy may be slightly higher.
No interactions have been reported between black cohosh and non-prescription drugs, other herbal supplements, or foods. However, because few reliable studies of black cohosh have been conducted, its possible interactions with drugs, foods, and other dietary supplements are not understood completely. Individuals interested in using black cohosh should discuss with a doctor or pharmacist all the prescription medications, non-prescription drugs, and dietary supplements they take before beginning black cohosh.
Some interactions between herbal products and medications can be more severe than others. The best way for you to avoid harmful interactions is to tell your doctor and/or pharmacist what medications you are currently taking, including any over-the-counter products, vitamins, and herbals. For specific information on how black cohosh interacts with drugs, other herbals, and foods and the severity of those interactions.
Should I take it?
Black cohosh grows in wooded areas as a tall perennial bush with jagged-edged leaves and long stalks of white flowers. It is named for its rough, dark roots and rhizomes--the parts used in making medicine. "Cohosh" is derived from an native North American word that means rough. Rhizomes are fleshy extensions of plant stems that run along or under the ground and often produce shoots and roots for new plants.
Black cohosh was introduced to European settlers by the native people of eastern and central North America. Native Americans used the juice of the plant to repel insects and they applied a salve of black cohosh to snake bites. They used a tea made from the dried roots for menstrual cramps and difficult childbirth. As a drink, black cohosh was also used for coughs and sore throats, as well as for upset stomach.
In 1986, the FDA concluded that not enough was known about black cohosh to include it on the list of herbal products generally recognized as safe (GRAS). Newly renewed interest in its possible effects has opened new clinical trials for the usefulness of black cohosh in treating several conditions. In Germany, it has been recognized for nearly 20 years as effective for relieving menstrual and menopausal complaints.
Dosage and Administration:
The most active chemical in black cohosh is believed to be a glycoside called 27-deoxyacetin. Glycosides are chemicals that decompose into a sugar and other substances. Many glycosides have medicinal effects. The activity of black cohosh may vary greatly from individual to individual, however. Additionally, black cohosh usually needs to be taken daily for several weeks before it reaches full effectiveness.
In Europe, the use of black cohosh is fairly common as both a prescription drug and an herbal supplement. Often, it is combined with other herbals, such as dong quai and red clover, that may have similar effects in the body. Commercial preparations of black cohosh alone include tablets that may be standardized to contain one mg of glycoside per 20 mg tablet. Standardization by the manufacturer should assure the same amount of active ingredient in every batch of the commercial preparation.
Standardization of herbal products is not required by the U.S. Food and Drug Administration (FDA), so not every product sold in the United States will contain the same amounts of active ingredients. Liquid extracts and tinctures of black cohosh are also available. Extracts are concentrated liquid preparations usually made by soaking chopped or mashed plant parts in a liquid such as alcohol, which is then strained to remove the solid plant parts. Tinctures are less concentrated than extracts, but they are prepared in similar ways.
A commercial black cohosh product has been introduced to the non-prescription market in the United States after years on the German market. Its manufacturer suggests that its use be limited to 6 months or less because no long-term studies have been done to evaluate longer therapy.
Dried roots or rhizomes of black cohosh can also be made into a tea that may be taken one time to three times a day. Rhizomes are fleshy extensions of plant stems that run along or under the ground and often produce shoots and roots for new plants. The tea is made by chopping or grating up to 2,000 mg (2 grams) of the dried roots or rhizomes, dropping them into boiling water, and allowing them to simmer for about 10 minutes. The tea is then strained to remove the solid particles before drinking it.
Typical doses are: Commercially available tablets 1 tablet to 4 tablets (20 mg to 80 mg) Twice a Day
Liquid extract 0.3 mL to 2 mL Daily
Tincture 2 mL to 4 mL Daily
Dried root/rhizome 300 mg to 2000 mg (0.3 gram to 2 grams) Daily
Black cohosh is used primarily by women to relieve hot flashes, mood swings, and other uncomfortable symptoms of menopause and to lessen menstrual cramps and bloating.
Individuals with liver conditions should avoid taking black cohosh, which may cause liver damage in rare cases. Because black cohosh may affect levels of the female hormone estrogen, it may cause uterine contractions; therefore, it should not be taken by pregnant women. Not much is known about how black cohosh affects children or whether it is passed to babies in breast milk, so women who are breast-feeding should not take black cohosh.
Large doses of black cohosh are reported to have resulted in:
Low heart rate
Temporary vision changes
Side effects commonly associated with taking black cohosh in any amount include:
Because it may interfere with estrogen in the body, black cohosh could lessen the effects of hormone replacement therapy or oral contraceptives.
Gaia Herbs Liquid Phyto Black Cohosh
Nature's Way's Black Cohosh