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Other common
name(s): traditional Chinese medicine, TCM, Chinese
herbs, Oriental medicine
Scientific/medical
name(s): none
Description
Chinese herbal medicine is a major aspect of traditional
Chinese medicine, which focuses on restoring a balance of energy, body,
and spirit to maintain health rather than treating a particular disease
or medical condition. Herbs are used with the goal of restoring balance
by nourishing the body.
Overview
Because of the large number of Chinese herbs used and the
different uses recommended by practitioners, it is difficult to comment
on Chinese herbal medicine as a whole. There may be some individual
herbs or extracts that play a role in the prevention and treatment of
cancer and other diseases when combined with conventional treatment.
However, more research is needed to determine the effectiveness of
these individual substances.
How is it promoted for use?
Chinese herbal medicine is not based on conventional Western
concepts of medical diagnosis and treatment. It treats patients' main
complaints or the patterns of their symptoms rather than the underlying
causes. Practitioners attempt to prevent and treat imbalances, such as
those caused by cancer and other diseases, with complex combinations of
herbs, minerals, and plant extracts.
Chinese herbal medicine uses a variety of herbs in different
combinations to restore balance to the body, such as astragalus,
ginkgo, ginseng, green tea, and eleuthero (also known as "Siberian
ginseng"). Herbal preparations are said to prevent and treat hormone
disturbances, infections, breathing disorders, and a vast number of
other ailments and diseases. Some practitioners claim herbs have the
power to prevent and treat a variety of types of cancer.
Most Chinese herbalists do not claim to cure cancer. They use
herbal medicine with conventional treatments prescribed by oncologists,
such as radiation therapy and chemotherapy. They claim that herbal
remedies can help ease the side effects of conventional cancer
therapies, control pain, improve quality of life, strengthen the immune
system, and in some cases, stop tumor growth and spread.
One aspect of Chinese herbal medicine aims to restore or
strengthen immunity and resistance to disease. Treatments undertaken
with this goal are called Fu Zheng or Fu Zhen and are given as
complementary therapy intended to reduce the side effects from
conventional Western anticancer treatments.
What does it involve?
In China, more than 3,200 herbs and 300 mineral and animal
extracts are used in more than 400 different formulas. Herbal
formulations may consist of 4 to 12 different ingredients, to be taken
in the form of teas, powders, pills, tinctures, or syrups.
Chinese herbal remedies are usually made up of a number of
herbs and mineral and animal extracts. Typically, 1 or 2 herbs are
included that are said to have the greatest effect on the problem being
treated. Other ingredients in the formula treat minor aspects of the
problem, direct the formula to specific parts of the body, and help the
other herbs work more efficiently.
With the increase in popularity of herbal medicine, many
Chinese herbs are now sold individually and in formulas. In the United
States, Chinese herbs and herbal formulas may be purchased in health
food stores, some pharmacies, and from herbal medicine practitioners.
Before choosing a mixture of herbs for a patient, the
traditional Chinese practitioner will typically ask about symptoms and
examine the patient, often focusing on the skin, hair, tongue, eyes,
pulse, and voice, in order to detect imbalances in the body.
What is the history behind it?
Native cultures all over the world have traditionally used
herbs to maintain health and treat illnesses. Chinese herbal medicine
developed as part of Chinese culture from tribal roots. By 200 BC,
traditional Chinese medicine was firmly established, and by the first
century AD, a listing of medicinal herbs and herbal formulations and
their uses had been developed.
The classic Chinese book on medicinal herbs was written during
the Ming Dynasty (1152-1578) by Li Shi-Zhen. It listed nearly 2,000
herbs and extracts. By 1990, the latest edition of The Pharmacopoeia of the
People's Republic of China listed more than 500 single
herbs or extracts and nearly 300 complex formulations.
As Western conventional medicine spread to the East, some
traditional Chinese medical practices began to be regarded as folklore.
However, since 1949, the Chinese government has supported the use of
both traditional and Western medicine. Chinese herbal medicine first
came to widespread attention in the United States in the 1970s, when
President Richard Nixon visited China. Today, at least 30 states
license practitioners of Oriental medicine and more than 25 colleges of
Oriental medicine exist in the United States.
What is the evidence?
Some herbs and herbal formulations have been evaluated in
animal, laboratory, and human studies in both the East and the West
with wide-ranging results. Research results vary widely depending on
the specific herb, but several have shown activity against cancer cells
in laboratory dishes and in some animals.
There is some evidence from randomized clinical trials that
some Chinese herbs may contribute to longer survival rates, reduction
of side effects, and lower risk of recurrence for some types of cancer,
especially when combined with conventional treatment. Many of these
studies, however, are published in Chinese, and some of them do not
list the specific herbs that were tested. Some of these journal
articles do not describe how the studies were conducted completely
enough to determine whether they use methods comparable to those used
in Western clinical research. However, there are some notable
exceptions, such as PC-SPES, a mixture including several Chinese herbs
that has been studied in considerable detail in U.S. clinical trials
(see the document PC-SPES).
More controlled research is needed to determine the role of Chinese
herbal medicine in cancer treatment and prevention.
Are there any possible problems or
complications?
These
substances may not have been thoroughly tested to find out how they
interact with medicines, foods, herbs, or supplements. Even though some
reports of interactions and harmful effects may be published, full
studies of interactions and effects are not often available. Because of
these limitations, any information on ill effects and interactions
below should be considered incomplete.
Because of the variety of herbs used in Chinese herbal
medicine, there is a potential for negative interactions with
prescribed drugs. Some herbal preparations contain other ingredients
which are not always identified. The U.S. Food and Drug Administration
(FDA) has issued a statement warning diabetics to avoid several
specific brands of Chinese herbal products because they illegally
contain the prescription diabetes drugs glyburide and phenformin. FDA
warnings have been issued for PC-SPES, and production of that product
was stopped because it contained the prescription drugs indomethicin,
diethylstilbestrol, and warfarin.
Similar concerns have been raised about Chinese herbal
products for other diseases, which have been found to contain toxic
contaminants and prescription drugs such as diazepam (Valium). Tests of
Chinese herbal remedies by the California Department of Health found
that nearly one third contained prescription drugs or were contaminated
with toxic metals such as mercury, arsenic, and lead. Concerns about
Chinese herbal products have been raised in other countries as well.
The Japanese Ministry of Health, Labour, and Welfare reported that some
Chinese herbal products contained contaminants that caused severe and
sometimes fatal liver and thyroid problems.
Of the more than 5,000 medicinal plant species in China, a
small number are potentially toxic to the human body. Toxic herbs may
mistakenly be harvested and shipped for herbal medicines and can cause
harmful reactions in those who take the medicines. In addition, the
herbal formulas used are often complex and difficult for manufacturers
and practitioners to formulate correctly. For example, in the case of
an herbal product intended to promote weight loss, manufacturers
confused 2 Chinese herbs with similar names and mistakenly used the
wrong one, which resulted in severe kidney damage that was fatal in
some cases.
Any herb can cause allergic reactions in a few people. Those
who are allergic to certain plants, including some plant-based foods,
may be more likely to react to herbs.
Although the long history of traditional Chinese herbal
medicine is sometimes interpreted as evidence of safety, it is
important to note that many of these herbs are no longer produced and
used as they were in the past. An herb may have been used safely under
the supervision of a traditional practitioner. However, if the same
herbs are used in higher doses or in doses of different concentrations,
perhaps over a longer period and without medical guidance, the risks
involved in taking those herbs change. In addition, toxic substances or
prescription drugs can be introduced during the manufacturing process,
either intentionally or inadvertently.
Practitioners of traditional Chinese medicine licensed by a
state board can provide advice on the safest sources for herbs. Because
some herbs used in traditional Chinese medicine may cause dangerous
interactions with conventional medications, patients should talk with
their doctors and pharmacists before using any of the herbs. Relying on
this type of treatment alone and avoiding or delaying conventional
medical care for cancer may have serious health consequences.
Additional Resources
More information from your American Cancer
Society
The following information on complementary and alternative
therapies may also be helpful to you. These materials may be found on
our Web site (www.cancer.org)
or ordered from our toll-free number (1-800-ACS-2345).
References
Au AM, Ko R, Boo FO, Hsu R, Perez G, Yang Z. Screening methods
for drugs and heavy metals in Chinese patent medicines. Bull Environ Contam Toxicol.
2000;65:112-119.
Boik J. Cancer
and Natural Medicine: A Textbook of Basic Science and Clinical Research.
Princeton, MN: Oregon Medical Press; 1995.
Cole MR, Fetrow CW. Adulteration of dietary supplements. Am J Health-Syst Pharm.
2003;60:1576-1580.
Ergil KV, Kramer EJ, Ng AT. Chinese herbal medicines. West J Med.
2002;176:275-279.
Ko RJ. Adulterants in Asian patent medicines. N Engl J Med.
1998;339:847.
Marcus DM, Grollman AP. Botanical medicines -- the need for
new regulations. N Engl
J Med. 2002;347:2073-2076.
National Institutes of Health. Alternative Medicine: Expanding
Medical Horizons: A Report to the National Institutes of Health on
Alternative Medical Systems and Practices in the United States.
Washington, DC: US Government Printing Office; 1994. NIH publication
94-066.
Traditional chinese medicine. University of Maryland Medical
Center Web site.
http://www.umm.edu/altmed/articles/chinese-medicine-000363.htm. Updated
December 1, 2002. Accessed June 4, 2008.
Note:
This
information may not cover all possible claims, uses, actions,
precautions, side effects or interactions. It is not intended as
medical advice, and should not be relied upon as a substitute for
consultation with your doctor, who is familiar with your medical
situation.
Last Medical Review: 11/01/2008
Last Revised: 11/01/2008
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