Black cohosh is popular as an alternative to hormonal therapy in the treatment of menopausal (climacteric) symptoms such as hot flashes, mood disturbances, diaphoresis, palpitations, and vaginal dryness. Several studies have reported black cohosh to improve menopausal symptoms for up to six months, although the current evidence is mixed.
Black cohosh (Cumicifuga racemosa). One of the best-studied traditional herbs for menopause, black cohosh is used to help alleviate some symptoms of menopause, including hot flashes. Black cohosh seems to work by supporting and maintaining hormonal levels, which may lessen the severity of hot flashes. Many women report that the herb works well but it isn’t effective for everyone. While any therapy that influences hormonal actions should be a concern, black cohosh does not appear to have estrogenic activity and thus may be safe for women with a personal or family history of breast cancer.
What is the history behind it?
Cohosh is a Native American word that means “knobby rough roots,” which describes the appearance of the plant’s roots. Native Americans used black cohosh to treat uterine disorders such as menstrual and menopausal symptoms, as well as other ailments, such as diarrhea, sore throat, arthritis, and general weakness. The herb has been approved in Germany for the same purposes for more than 50 years and is commonly prescribed in other European countries.
How does it work?
The root of black cohosh is used for medicinal purposes. Black cohosh root contains several chemicals that might have effects in the body. Some of these chemicals work on the immune system and might affect the body’s defenses against diseases. Some might help the body to reduce inflammation. Other chemicals in black cohosh root might work in nerves and in the brain. These chemicals might work similar to another chemical in the brain called serotonin. Scientists call this type of chemical a neurotransmitter because it helps the brain send messages to other parts of the body.
Black cohosh root also seems to have some effects similar to the female hormone, estrogen. In some parts of the body, black cohosh might increase the effects of estrogen. In other parts of the body, black cohosh might decrease the effects of estrogen. Estrogen itself has various effects in different parts of the body. Estrogen also has different effects in people at different stages of life. Black cohosh should not be thought of as an “herbal estrogen” or a substitute for estrogen. It is more accurate to think of it as an herb that acts similar to estrogen in some people.
How much black cohosh should you take?
For menopausal symptoms, the dose of black cohosh used in studies has been 20-40 milligrams tablets of a standardized extract taken twice a day. More than 900 milligrams a day of black cohosh is considered an overdose. There is some reference in studies to tinctures of black cohosh, with a dose range of 2-4 milliliters daily. Directions for taking black cohosh in other forms will vary. Some experts say that no one should take black cohosh for more than six months at a time.
Black Cohosh and Labor
According to the National Institutes of Health, black cohosh is a plant that has been used for many years as an herbal treatment for a variety of female health conditions. Black cohosh is often used by midwives and other health practitioners to induce labor in women who are nearing or have passed their due date. The herb may help regulate and strengthen contractions, while promoting cervical ripening
A 2005 study of 304 women found that, compared to a placebo (inactive or sham pill), black cohosh helped symptoms of menopause. It seemed more effective for women whose symptoms had begun recently than for those who had been post-menopausal for a longer time.
On the other hand, a 2006 study of 351 women found that menopausal symptoms were helped by hormone therapy but not by black cohosh (either alone or with other herbs). Clinical trial results published in 2008 reported no difference between black cohosh and placebo regarding vaginal dryness, menstrual irregularity, female hormones, or the structure of vaginal cells in Pap test samples.
Another study done in 2009 compared black cohosh to placebo, conventional hormone therapy (estrogen and progesterone), and red clover (another popular herb for the relief of menopausal symptoms). The study looked at 89 healthy women who were randomly assigned to one of the 4 groups and did not know which treatment they were getting. The study found that black cohosh was actually significantly less effective than placebo in reducing symptoms. But the standardized extracts used in the study seemed to be safe for the participants during the 12 months they were followed.