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by Steven Foster
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. 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 at least
eighteen species. Collectively, they are commonly known as
bugbanes, primarily referring to the European species, C.
europaea and an Asian representative C. foetida, which have
strong, unpleasant smell, earning it a reputation as an insect-repelling
plant. The genus name Cimicifuga, itself, honors this 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 bugane. They have been used
independently as insect repellents throughout their extensive
ranges from India to western Europe to eastern Siberia. The
leaves of 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 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.
It was a Cincinnati physician, Dr. John
King, ( 1813-1893), who championed the use of black cohosh.
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.
Modern Use
Scientific research on black cohosh
began with investigations of its chemistry in the early twentieth
century. Clear attribution of biological activity to a single
chemical component remains illusive. It is believed 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 50
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.
Black Cohosh Today
Used in Europe for over 60 years, with
experience in over 1.5 million cases for the treatment of
menopausal symptoms, 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 at least eleven recent controlled clinical studies,
along with acute toxicity studies which help to confirm 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." The
German authorities suggest a daily dose of a liquid extract
(with 40-60 percent alcohol) equivalent to 40 mg of the dried
root. Transient gastric discomfort is the only side effect
reported by the German authorities. 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.
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