Black cohosh is a freestanding perennial plant that is native to the eastern parts of North America. It can be found as far south as Georgia and as far north as Maine.
Black cohosh is grown as an ornamental wildflower and can reach up to 3 meters in height. In the wild, it typically grows in partial shade out of rich soil. The flowers bloom from June through September and are thought to be pollinated by flesh flies.
Common Names for Black Cohosh
- Black snakeroot
- Squaw root
- Rattle top
- Frauenwurzel (Germany)
- Actee a grappes (France)
Black Cohosh Extract-Traditional Uses
Native Americans used black cohosh extract for general malaise, symptoms of menopause, kidney problems, malaria, rheumatism, and most well known, to relieve menstrual symptoms and hot flashes. Black cohosh was also used by the American colonists to treat conditions such as bronchitis, hot flashes, fever, amenorrea, itch, snake bites, uterine disorders, yellow fever, symptoms of menopause, and hysteria. The Cherokee and the Iroquois also used black cohosh extract infused in an alcohol tincture for the treatment of coughs, colds, and fatigue. Another extract version of this tincture was also used in steam baths and soaks for the treatment of rheumatism.
The rhizome of black cohosh extract is considered by many herbalists to be a natural astringent, antispasmodic, antitissive, aphrodisiac, expectorant, sedative, diuretic, and tonic. Black cohosh extract was the main ingredient in Lydia Pinkham’s Vegetable Compound, a popular patent remedy which was sold in the early 20th century for menstrual problems. Black cohosh extract was also viewed as a remedy for chorea and rattlesnake bites , and has been used for different infantile disorders such as diarrhea and whooping cough.
Black cohosh was officially listed in the United States Pharmacopoeia from 1820 to 1920. Patent remedies containing black cohosh extract are currently available in Europe, Australia, and South Africa for the treatment of PMS, symptoms of menopause, postmenopausal symptoms, hot flashes, cough, fluid retention, irritability, and pain and inflammation.
Current detailed accounts of the use of black cohosh extract for symptoms of menopause and hot flashes date back to the medical practices of the Eclectics. Black cohosh came into widespread use in the mid 1850′s in the United States. It was a very popular treatment and was given a place in the American Eclectic Dispensatory published in 1854. It was used for rheumatiod muscular pains, neuralgic pain, muscular pain, menstrual pain, hot flashes, symptoms of menopause, headache, and inflammation.
A preparation of fresh rhizomes was considered helpful before, during, and after labor, and was commonly given in small doses in the final four weeks of pregnancy as a partus preparator. Black cohosh extract was believed to reduce irritability in the uterus and false labor. The Eclectics wrote of it’s effectiveness in women with a history of complications during labor, and in cases where the uterine wall was lax. A report written in 1885 involving 160 childbirths stated that black cohosh extract was mildly sedating, reducing discomfort in the first stage of labor, increased rhythmicity of contractions in the second stage of labor, but specifically relaxed the cervical tissue, reducing lacerations.
Menopause–Black Cohosh Clinical Studies
A randomized, double blind, placebo controlled study was conducted in a group 85 women with hot flashes. While there were no significant differences between the lab results of the 2 groups, the black cohosh extract group did show a significant decrease in their amount of sweating. No adverse effects were reported by the black cohosh group in this study. Just one on the long list of black cohosh benefits.
The vast majority of clinical studies done to this date on black cohosh extract for symptoms of menopause and hot flashes have been open label studies, or controlled trials without a placebo group. Though they appear to be successful, more research is needed. This is expected to change soon because black cohosh extract is the #1 selling natural remedy for menopausal symptoms in the US.
A randomized, placebo controlled, double blind study was conducted in 80 female volunteers suffering from symptoms of menopause, including hot flashes. For 12 weeks, all participants were given either black cohosh extract, estrogen, or a placebo. To measure effectiveness, the study utilized the 14 point Hamilton Anxiety Scale to measure the amount of emotional disturbance, and the Kupperman Menopausal Index to access mainly neurovegatative complaints. Before the study, all participants were diagnosed to have moderate to severe menopausal symptoms, including hotflashes.
After 12 weeks of treatment, the black cohosh group showed a significant decrease in median Hamilton Anxiety Scale Scores as compared to the estrogen and placebo group. The study showed that results were apparent after only 4 weeks of treatment. The black cohosh group also showed a significant increase in emotional and psychological parameters as compared to the placebo group. The number of average hot flashes dropped from 5.1 to 3.1 per day in the placebo group, 5.2 to 3.2 per day in the estrogen group, and 4.9 to .7 per day in the black cohosh group.
It was concluded that black cohosh extract was an effective, all natural treatment for the symptoms of menopause, without the side effects of hormone replacement therapy, and fit the requirements for a first choice therapy.
The effects of black cohosh extract were compared with a placebo in an open controlled study on LH and FSH secretion in 110 menopausal women. None of the women had taken any type of HRT in the previous 6 months. After a period of 8 weeks, levels of LH, but not FSH, were greatly reduced in the patients taking black cohosh extract. The FSH remained similar in both groups.
An open, retrospective study was published in Germany in 1982. In total, 131 general practitioners provided information on 629 female patients with menopausal complications. Significant improvements in neurovegatative complaints (hot flashes, headaches, profuse sweating, heart palpitations, ringing in the ears), and emotional disturbances (irritability, anxiety insomnia, and depression) were observed in the black cohosh group.
After 6 to 8 weeks, all symptoms were abated in approximately 40% to 50% of the patients, and were significantly improved in 30% to 40% of patients. Overall improvement rates ranged from 76% to 93% of patients. This study showed clear and significant benefits from black cohosh extract to relieve the symptoms of menopause. No major side effects were reported, and it was found that adding St. John’s Wort to black cohosh had a synergistic effect on psychological symptoms.
Black Cohosh Dosage
The preparation used in the above mentioned studies is referred to as Remefemin. It is a standardized extract containing triterpine glycosides calculated as 27- deoxyactein (1mg/capsule). The normal dose has been 2 capsules, twice daily (equal to 4 mg triterpene glycosides per day). Dosages 2 or 3 times this amount have been used in some studies. But recent studies from the makers of Remifemin suggest that half of this dose is just as effective.
The British Herbal Compendium suggests a dosage of 40-200 mg dried rhizome, or 0.4-2 ml of a 1:10 60% ethanol tincture; however The British Phamacopoeial Compedium recommends a dose of 2-4 mg of the above mentioned tincture. If you are considering taking black cohosh extract as a treatment for menstrual or menopausal symptoms, it is recommended that you follow the instructions listed by the manufacturer, or consult a holistic doctor trained in herbal therapies. The effective range for black cohosh dosage varies quite a bit.
Black Cohosh Side Effects
The only reported black cohosh side effects have been mild gastrointestinal discomfort.
Black cohosh has commonly been used in conjunction with standard estrogen therapies. A preparation of black cohosh extract, estrogen therapy, and St.John’s Wort exhibited a very good tolerability in 99% of patients going through menopause.
It has been recommended that pregnant women don’t take black cohosh extract, as no information has been documented of the safety of black cohosh in pregnant women.
It has also been recommended that women who are breastfeeding do not take black cohosh because no information is available as to the safety for breastfeeding infants.
The German Commission E recommends that the period of use of black cohosh extract should not exceed 6 months, based on the lack of long term toxicology studies; however, no such complications have been found.
Black cohosh extract has been shown to be a safe and effective treatment for symptoms of menopause and hot flashes; however, it is always wise to consult a licensed medical professional that is well experienced in holistic and herbal therapies.
References: Mckenna D., Jones K., Hughes K., w/Humphrey S., Botanical Medicines : The Desk Reference for Major Herbal Supplements-Second Edition, New York, London, Oxford, 2002 37-64