Black cohosh Cimicifuga racemosa is equally at home in the perennial border as it is in its shaded haunts in the eastern deciduous forest. Pre-colonial botanical observers in America couldn't help but notice the handsome, robust foliage, with the tall spikes of brilliant white flowers, waving like a flag to attract attention. Native American groups of eastern North America looked deeper than its obvious beauty, believing that the thick, knobby, resin-scented roots must hold medicinal value. Black cohosh fits into several categories including woodland wildflower, garden perennial, and medicinal herb. Backed by an intriguing botanical, horticultural, and medicinal history, a new generation of baby boomer women - at the steps of menopause - are discovering that this traditional Indian remedy for female conditions is emerging as a new treatment for symptoms associated with menopause, backed by modern clinical research. Black cohosh is a rising star on the herbal horizon.
Origins
Black cohosh is a
member of the buttercup family found in rich woods
of the eastern deciduous forest from southern
Ontario south to Georgia, west to Arkansas, north
to Wisconsin. This perennial woodland plant likes
the deep shade of moist hillsides, the home of
other important medicinal plans such as goldenseal
and ginseng. It has robust, three-divided leaves,
with three-lobed terminal leaflets. The middle lobe
of the sharply-toothed leaflets is the largest. The
plant is little-noticed until it sends up its tall
spikes of showy white flowers, three to eight feet
tall. Petals are not to be seen; the chief feature
is tufts of conspicuous stamens surrounding the
pistil in the center. In begins blooming in May in
the southern part of its range, continuing to
flower into September in more northerly
regions.
Black cohosh was first described by botanists in 1705. By 1732, it had been introduced into English gardens as a hardy ornamental perennial. To this day, it is more widely grown in European gardens than in America. The root is the part of the plant used in herbal traditions. Most of the root is wild-harvested, while some is grown commercially in Europe.
The genus Cimicifuga includes eighteen species, one of which is native to Europe, six from North America, and the remainder from northeast Asia. Collectively, they are commonly known as bugbanes, primarily referring to the single native European species, C. europaea and an Asian representative C. foetida, which have strong, unpleasant smelling herbage, earning it a reputation as an insect-repelling plant. The genus name Cimicifuga, itself, honors this olfactory observation. It comes from the Latin cimex meaning bug (specifically the bed bug Cimex lectularius) and fugare "to drive-away" in reference to the insect-repelling attributes. These species are also known by the names bugwort or bugbane. They have been used independently as insect repellents throughout their extensive ranges from India to western Europe to eastern Siberia. The herbage of the American black cohosh does not possess a strong odor.
Historical
Development
American Indian groups of eastern North America
were using the root of black cohosh to treat female
conditions and for rheumatism, long before
Europeans landed on American shores. The Delaware,
moved to the Indian Territories of modern Oklahoma
a century ago, used black cohosh in combination
with other herbs as a female tonic. The Iroquois of
New York used a strong tea of the root as a foot
bath, soaking the feet while bathing sore, stiff
areas of the body to treat rheumatism. The Cherokee
are said to have used the roots to treat rheumatism
and various female conditions. They also valued it
as a tonic and diuretic. Early medical authors note
that use of the plant was learned from native
Americans.
The importance of black cohosh as a medicinal plant was recognized in the first works on American herbs, dating back to 1801. The root was an important folk medicine among American Indian groups and early settlers for menstrual irregularities and as an aid in childbirth. It was widely prescribed by physicians in nineteenth century America, where it had a great reputation as an anti-inflammatory for arthritis and rheumatism, and played an important role for normalizing suppressed menses, painful or difficult menses, and to relieve pain after childbirth. It was also used for nervous disorders. The root was an official drug of the United States Pharmacopoeia from 1820 to 1926.
In historical works, information on the herb can be found under several names. Early editions of the United States Pharmacopoeia gave its official name as "black snakeroot," a name that persisted in medical books into the 1890s. Eclectic medical practitioners of the late nineteenth and early twentieth centuries knew it by the name "macrotys" both a botanical and common name that was never widely recognized, and is lost in obscurity.
It was the eclectics who championed the use of black cohosh, particularly Dr. John King, (1813-1893), who also first brought Echinacea to the attention of the medical community. Black cohosh was more important to King than Echinacea, since he was a professor of obstetrics at the old Eclectic medical college in Cincinnati (which closed its doors in 1943). He spoke about black cohosh to his students as his "favorite remedy. " He had used it in his own clinical practice from 1832 until his death, as an important remedy in both acute and chronic cases of rheumatism and related inflammatory conditions, plus various lung and nervous affections. King recognized it as his primary treatment "in abnormal conditions of the principal organs of reproduction in the female."
If King had not been such a strong proponent of the herb, it may have faded away into obscurity. Like several important herbs, such as Echinacea and saw palmetto, in the early part of this century, the eclectics' extensive use and advocacy of black cohosh attracted the attention of the German medical community. As use of herbs faded in American medicine by the 1930s, the Germans picked-up the reins and catapulted these herbs into modern use. Once again, we turn to Germany for modern experience with this useful traditional American Indian remedy.
Modern
Use
Scientific research on black cohosh began with
investigations of its chemistry in the early
twentieth century. Using the comparatively crude
isolation methods of the day, chemists found
phytosterin, isoferulic acid, salicylic acid,
sugars, tannins and fatty acids in the roots. A
study published in 1944 first attributed
estrogenic-like activity to the roots in laboratory
experiments with mice. In the 1950s and 60s further
chemical work identified glycosides such as acetin,
cimicifugoside, and 27 deoxyacteine as compounds
that may contribute to the root's effects on female
reproduction. In the early 1980s an isoflavone
called, formononetin was also identified. Clear
attribution of biological activity to a single
chemical component remains illusive. It is believed
that at least three different chemical fractions
soluble in alcoholic extracts may contribute to
positive benefits in the treatment of menopausal
symptoms.
By the mid 1950s sufficient scientific evidence, coupled with extensive clinical experience, made black cohosh preparations widely accepted and prescribed by German gynecologists, primarily as a an alterative to hormone treatment in menopausal disorders. By that time, hormonal replacement therapies were already recording unwanted side effects in a large number of patients. By 1962 at least 14 clinical studies (though not controlled clinical studies in the modern sense) had been published on the use of black cohosh products in over 1500 patients. These studies, some over 40 years old, began to establish clear scientific evidence for the safety and effectiveness of black cohosh in the treatment of premenopausal and menopausal symptoms including a reduction in the severity and duration of hot flashes along with an improvement of depressive moods.
Clinical
studies
Today in Germany, black cohosh preparations are
used in the treatment of menopause to improve
symptoms such as hot flashes, depression and sleep
disturbance. In 1985, German researchers found that
black cohosh produced an effect on serum
concentrations of pituitary hormone levels,
including a significant and selective reduction of
luteinizing hormone (while not significantly
effecting levels of prolactin and follicle
stimulating hormone). Hot flashes have been linked
to a significant spike in the release of
luteinizing hormone. The study provided a way to
measure the endocrinological, particularly
estrogenic effects, of black cohosh. A follow-up
study failed to identify a single chemical
component responsible for the luteinizing hormone
suppressing activity, leading researchers to
believe that synergistic effects of several
chemical fractions were involved in the biological
activity, competing with estradiol for binding
sites on receptor proteins.
Recent clinical studies have shed further light on the herb's effects. A 1982 an open multi-center German clinical study involving data on 629 patients from 131 general practitioners and gynecologists was published. The researchers found that after six to eight weeks of treatment, 80 percent of patients had beneficial effects. In over 49 percent of volunteers there was dramatic relief in reduction of hot flashes, sweating, headache, vertigo, palpitation and tinnitus, while over 39 percent reported significant reductions of these symptoms, along with a lessening of nervousness, irritability and depression. Side effects (unspecified gastrointestinal problems) were reported for seven percent of the women. None of the side effects were serious enough to discontinue treatment.
A 1987 German double blind study compared estrogen replacement therapy with black cohosh for three months in eighty women. Thirty received a black cohosh extract (8 mg per day), 30 received black cohosh, and 20 volunteers received placebo. The black cohosh preparation was well-tolerated and produced significant improvement in the test parameters, which included menopausal symptoms as measured by the Kupperman Menopausal Index, depressive symptoms as measured by the Hamilton Anxiety Scale, as well as its effect on vaginal epithelium cells. The author concluded that black cohosh not only produced safe and efficacious results, but compared to estrogen replacement therapy, is suitable as a treatment of choice in menopausal symptoms.
A 1988 German clinical study compared treatment with three different estrogen therapies and an extract of black cohosh in 53 women (under 40 years of age). Many had experience surgical removal of an ovary leading to development of menopausal-like symptoms. Treatment with the black cohosh extract was found to be comparable to treatment with the three conventional drug preparations tested. The authors concluded that in cases where conventional hormone therapy is contraindicated, the plant extract is the therapy of choice.
In 1991 another German research group conducted a study involving 110 menopausal women. They demonstrated for the first time in a clinical trial that the extract selectively suppresses luteinizing hormone secretion in menopausal women, and further confirms an estrogenic effect of the alcoholic fractions of black cohosh root.
These limited clinical studies provide encouraging results setting the stage for further, larger scale controlled clinical studies in the future.
Black
Cohosh Today
Used in Europe for over 40 years, with
experience in over 1.5 million cases, black cohosh
is again becoming known in its native land as a
possible alternative for reducing unpleasant
symptoms associated with menopause. Efficacy and
safety are confirmed by long-term clinical
experience, as well as recent controlled clinical
studies, along with acute toxicity studies which
help to corroborate its safety.
In Germany, black cohosh is covered by a positive monograph of the German Commission E. Products can be labeled for "premenstrual discomfort, dysmenorrhea or climacteric (menopausal) neurovegetative ailments." Reported activities are an estrogen-like action, binding to estrogen receptors and suppression of luteinizing hormone. The German authorities suggest a daily dose of a liquid extract (with 40-60 percent alcohol) equivalent to 40 mg of the dried root. Typically, the product on which the vast majority of studies have been conducted is a concentrated extract delivered at a dose of 8 mg (4 mg twice per day). Transient gastric discomfort is the only side effect reported. Presumably because long-term toxicity studies have not been conducted, duration of use is limited to six months.
Black cohosh will become of increasing interest to women looking for an alternative to estrogen therapy in the treatment of menopausal symptoms. Not only is it widely used in Europe, black cohosh and related species have a long history of use in both Asia and North America. Among women's herbs, black cohosh is the most important rising star.