Black cohosh is an herbal supplement that has been used as an alternative therapy for hormone replacement patients, including menopausal women and those with menstruation problems. It is believed by some scientists that components in the herb behave similarly or the same as natural estrogen. Past studies have shown the herb is safe and effective for up to six months, according to MayoClinic.com. More recent studies have concluded that the mechanism by which the herb reacts with and affects estrogen receptors, as well as long-term safety, is largely unknown.
Pharmacology and Mechanism
According to the University of Maryland Medical Center (UMMC), black cohosh may contain plant-based estrogens, which are called phytoestrogens. It was originally believed that black cohosh mimics the behavior of estrogen and binds to estrogen receptors, thus behaving as prescription hormone replacement drugs. However, more recent studies have not been able to prove that this is how the herbal supplement works. In fact, some doctors believe the herb may actually interfere with naturally occurring estrogen in the body, thereby reducing its regulatory effects on menopause and menstruation. Patients who do not wish to take hormone replacement prescriptions may take black cohosh under the direction of their physician, but clinical research testing the effectiveness of the herb is mixed.
Hot Flashes
Black cohosh has been used by Native Americans and Europeans for many years to treat hot flashes, a common symptom of menopause, though research examining this treatment is conflicting at best. The UMMC reports that some studies have shown it to be more effective than traditional drugs, and others have shown it to be completely ineffective. Additionally, BreastCancer.org states that studies conducted in women with breast cancer experienced no fewer hot flashes when taking the supplement than those that were given a placebo.
Cancer Risk
BreastCancer.org also reports that a 2007 study claimed that women taking black cohosh experienced a 61 percent reduction in risk of developing breast cancer, though these findings have yet to be supported. The American Cancer Society states that research examining claims that black cohosh can help treat cancer is currently lacking.
Arthritis and Osteoporosis
The substances found in black cohosh also present potential in treatment of nonmenopausal symptoms and conditions. The UMMC notes that the phytoestrogens in black cohosh may thwart bone loss associated with osteoporosis. Some studies have suggested that a combination of herbs including black cohosh can help to treat osteoarthritis symptoms -- perhaps due to the anti-inflammatory effects of isoferulic acids, another substance found in the herb; however, research using black cohosh for treatment of these conditions in humans is still minimal.
Dangers
Due to scant research and conflicting findings, if you have previously been diagnosed with breast or any other cancer, you should speak to your doctor before taking black cohosh. The herb interacts with chemotherapy treatments and other herbs and should also not be taken by pregnant or lactating women. Black cohosh interacts with tamoxifen, a prescription estrogen replacement drug commonly used by menopausal women, and some patients may be allergic to the plant or experience side effects of nausea, dizziness and racing heartbeat.
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