Traditional Chinese Herbal Medicine
• Aristolochia Clematis, Banxia Houpo Tang, Biminne, Bing Gan Tang, Bupleurum, Minor, Chinese Herbs, Chinese Patent Remedies, Coptis Formula, Daio-Kanzo-To, Fuzheng Jiedu Tang, Hange Koboku-To, Herbs, Chinese, Hochu-Ekki-To, Jianpi Wenshen Recipe, Kampo, Magnolia and Pinelliae Formula, Minor Bupleurum, PC-SPES, Saiboku-To, Saiko-Keishi-To, Shakuyaku-Kanzo-To, Shosaiko-To, Sho-Seiryu-To, Shuang Huang Lian, Toki-Shakuyaku-San, Xuezhikang, Yi Zhu Decoction, Zemaphyte
• Liver Conditions
The system of herbal medicine that developed in China differs in several significant ways from European herbal medicine. The most obvious difference is that the Western herbal tradition focuses on “simples,” or herbs taken by themselves. In contrast, traditional Chinese herbal medicine (TCHM) makes almost exclusive use of herbal combinations. More importantly, these formulas are not designed to treat symptoms of a specific illness; rather, they are tailored specifically to the individual according to the complex principles of traditional Chinese medicine. For this reason, TCHM is potentially a deeply holistic healing approach. On the other hand, it is both more difficult to use and to study than its Western counterpart.
TCHM is widely used in Asian countries, both in its traditional holistic form and in a simplified disease-oriented version. There have been a few properly designed scientific trials of TCHM, but the evidence base remains highly inadequate. In addition to questions regarding effectiveness, there remain serious safety concerns to be resolved.
History of Chinese Herbal Medicine
Chinese herbal medicine has a long historical tradition, although it is not quite as ancient as popularly believed. Ancient herbology in China focused on potions whose function was part medicinal and part magical, and it lacked a substantial theoretical base. Sometime between the second century B.C.E. and the second century A.D., the theoretical foundations of traditional Chinese medicine were laid, but the focus was more on acupuncture than on herbs. 1 Only by about the 12th century A.D. were the deeper principles of Chinese medicine fully applied to herbal treatment, forming a method that can be called TCHM. This was further refined and elaborated during various periods of active theorizing in the 14th through the 19th centuries. Western disease concepts entered the picture in the 20th century, leading to further changes.
In China today, TCHM is used alongside conventional pharmaceutical treatment. Considerable attempts have been made to subject TCHM to scientific evaluation; however, most of the published Chinese studies on the subject fall far short of current scientific standards. (For example, they generally lack a
In neighboring Japan, a variation of the TCHM system known as Kampo has become popular, and the Japanese Health Ministry has approved many Kampo remedies for medical use. The scientific basis for these remedies remains incomplete, but several studies of minimally acceptable quality have been reported.
Principles of Traditional Chinese Herbal Medicine
Even a basic introduction to the principles of TCHM exceeds the scope of this article. Consider the following nothing more than a taste of this vast medical system.
According to the principles of all Chinese medicine, health exists when the body is balanced and its energy is freely flowing. The term “energy” refers to Qi, the life energy that is said to animate the body. The term “balance” refers to the relative factors of yin and yang—the classic Taoist opposing forces of the universe. Yin and yang find their expression in various subsidiary antagonists such as cold vs. heat, dampness vs. dryness, descending vs. ascending, at rest vs. active, and full vs. empty.
In an ideal state, yin and yang in all their forms are perfectly balanced in every part of the body. However, external or internal factors can upset this balance, leading to disease. Chinese medical diagnosis and treatment involves identifying the factors that are out of balance and attempting to bring them back into harmony. Diagnosis is carried out by means of “listening” to the pulse (in other words, taking the pulse with extraordinary care and sensitivity), observing and palpating various parts of the body, and asking a long series of questions.
It is important to realize that diagnosis according to TCHM differs greatly from Western diagnosis. To understand this, consider two hypothetical patients with the single Western diagnosis of migraine headaches. The first might be said to have “dryness in the liver and ascending Qi,” while another might be diagnosed with “exogenous wind-cold.” Based on these differing diagnoses, entirely different remedies might be applied. In other words, there is no such thing as a TCHM remedy for migraines per se; rather, treatment must be individualized to the imbalance determined by traditional theory.
The herbal formulas used in TCHM consist of four categories of herbs: ministerial, deputy, assistant, and envoy. The ministerial herb addresses the principal pattern of the disease. Deputy herbs assist the ministerial herb or address coexisting conditions. Assistant herbs are designed to reduce the side effects of the first two classes of herbs, and envoy herbs direct the therapy to a particular part of the body. For example, in the case of “dryness in the liver and ascending Qi” described above, an herbalist might employ a ministerial herb to reverse ascending Qi, a deputy herb to exert a moistening effect, an assistant herb to prevent the stagnation of Qi (Qi stagnation is said to be a side effect of moistening herbs), and an envoy to carry these effects to the liver.
TCHM remedies can also be designed to fit all common causes of migraines simultaneously, mostly by multiplying the number of ingredients. Practitioners of TCHM frown upon this “one-size-fits-all” approach, but it is often popular among consumers and easier to test scientifically.
Types of Chinese Herbal Remedies
To use Chinese herbal medicine in the most traditional fashion, you must visit an herbalist’s shop. There, experienced herb preparers will chop, grind, fry, and slice dried herbs according to the prescription given by an experienced herbalist. You will walk home with a packet of dried herbs that need to be prepared according to the instructions, which typically involve adding water, boiling for several hours in a ceramic pot, pouring off the liquid, adding more water, and repeating the process twice more. Certain herbs are supposed to be added right at the end, while others require extra-long preparation.
If you don’t wish to carry out such a complex process, or if a classic herbal shop is not available, you may wish to move one step away from tradition and purchase an already-prepared Kampo formula. There are several hundred such formulas designed to match the most commonly seen forms of imbalance. Available in powder, capsule, or tablet form, they can be used much more conveniently than fully traditional herbs. Many Kampo combinations are licensed in Japan and are manufactured there on a large scale by reputable manufacturers.
The lowest level of TCHM, scarcely deserving the name at all, involves so-called Chinese Patent Remedies, which consist most commonly of tiny brown spheres in small brown bottles. They are marketed both for classical imbalances and western disease categories. Patent remedies are inexpensive and widely available. However, there have been so many scandals involving dangerous contaminants not listed on the label that we recommend avoiding this form of treatment entirely. (See Safety Issues .)
In the West, herbal medicine is part of folk medicine. However, in China there is a distinct tradition of Chinese folk medicine that is separate from the orthodox, rather academic TCHM approach. In this Chinese folk medicine, herbs are used more simply, somewhat in the manner of Western herbal medicine. Herbs most commonly used in this manner include
Besides herbs, substances that we might consider supplements are utilized in TCHM. These include extract of human placenta,
What Is Chinese Herbal Medicine Used for Today?
In the traditional system of Chinese herbal medicine, herbal formulas can be used to treat virtually any condition. Some of the most common uses in China include liver disease ( hepatitis
What Is the Scientific Evidence for Traditional Chinese Herbal Medicine?
To establish the effectiveness of a treatment, it must be put through a double-blind, placebo-controlled trial
The first problem involves diagnosis. As described above, there is no such thing as a TCHM remedy for migraine headaches, for example. Each person with migraines receives individualized treatment. This introduces an extra wrinkle for experimenters.
The best way to address this issue is as follows. People are chosen to participate in a study based on a Western diagnosis. Next, all participants are diagnosed by a classic herbal practitioner and prescribed a formula specific to their individual constitutions according to the principles of TCHM. Finally, another party steps in and provides participants with either the real formula or a placebo formula, under conditions whereby neither practitioners nor participants know which is which.
Other studies utilize a fixed remedy for all participants, in hopes that it will still prove effective on average. Such an approach doesn’t really test the effectiveness of true TCHM; rather, it tests a much-simplified form of it. Still, trials of this type are valid as far as they go.
Numerous other studies simply involve enrolling people with a certain condition and giving each participant an herbal remedy. Researchers then record the extent of improvement. Such
Finally, many of these studies were performed in China, and, up to the time of this writing, research on Chinese medicine conducted in China generally falls far short of modern scientific standards of rigor.
Hepatitis is a serious problem in many Asian countries, and conventional care leaves much to be desired. For this reason, herbal remedies are widely used.
The herbal combination Shosaiko-to (Minor Bupleurum) has been approved as a treatment for chronic hepatitis by the Japanese Health Ministry, and it enjoys wide use in that country and elsewhere.
Other Chinese herbal remedies have been tested as adjuncts to conventional interferon treatment with promising results.
If you are on interferon therapy, you should not use Chinese herbal formulas (or any herbs or supplements) except under the supervision of a physician (see
Combination Chinese herbal therapies have also shown a bit of promise for the treatment of chronic hepatitis; tested formulas include Bing Gan Tang, Yi Zhu decoction, Fuzheng Jiedu Tang, and Jianpi Wenshen recipe.
There have been numerous cases of hepatitis and other forms of liver injury
by Chinese herbs. See
Shosaiko-to, mentioned in the previous section, has also shown some promise for preventing liver cancer and liver fibrosis in people with
Irritable Bowel Syndrome
In a double-blind, placebo-controlled trial, 116 people with
The Kampo formula known as Daio-kanzo-to is a mixture of rhubarb and licorice. In a 2-week, double-blind, placebo-controlled trial, 132 people complaining of constipation were randomly assigned to one of three groups: placebo, low-dose Daio-kanzo-to, or high-dose Daio-kanzo-to.
In a double-blind, placebo-controlled trial, 220 people with
Another combination herbal therapy has shown promise for allergic rhinitis as well. In a 12-week, double-blind, placebo-controlled trial, 58 people with allergic rhinitis were given either placebo or an 11-herb combination remedy called Biminne.
- Rehmannia glutinosa
- Scutellaria baicalensis
- Polygonatum sibiricum
- Ginkgo biloba
- Epimedium sagittatum
- Psoralea corylifolia
- Schisandra chinensis
- Prunus mume
- Ledebouriella divaricata
- Angelica dahurica
- Astragalus membranaceus
Benefits have been seen in small studies of other formulations as well.
A double-blind, placebo-controlled study of 96 people with
The Kampo remedy Shakuyaku-kanzo-to is a combination of peony root and
In a double-blind trial of 40 women complaining of
In a 2008 review of 39 randomized controlled trials involving a total of 3,475 women, researchers concluded that the use of traditional Chinese herbs shows some promise in for the treatment of menstrual pain. However, firm conclusions were not possible due to the wide variability of study design and herbs used, as well as the poor quality of many of the studies.
A double-blind study of more than 200 people evaluated the effectiveness of Coptis Formula (a traditional combination therapy) with or without the drug glibenclamide for the treatment of
The Kampo remedy Saiboku-to has been approved by the Japanese Health Ministry for the treatment of
A Chinese study using a proprietary formulation reported benefits as well.
A Chinese herbal mixture sold under the name Zemaphyte has shown promise as a treatment for
- Ledebouriella seseloides
- Potentilla chinensis
- Akebia clematidis
- Rehmannia glutinosa
- Paeonia lactiflora
- Lophatherum gracile
- Dictamnus dasycarpus
- Tribulus terrestris
- Glycyrrhiza uralensis
- Schizonepeta tenuifolia
However, a subsequent study of similar design performed by a different research group failed to find significant benefit with Zemaphyte.
In a 12-week, double-blind study, a different traditional Chinese herbal formula also failed to prove more effective than placebo for treatment of eczema.
A topical ointment known as Tiger Balm is a popular treatment for headaches and other conditions. Tiger Balm contains camphor, menthol, cajaput, and clove oil. A double-blind study enrolling 57 people with acute
Chinese herbal therapies have been investigated for the treatment of
In another double-blind, placebo-controlled trial, 68 HIV-infected adults were given either placebo or a preparation of 35 Chinese herbs for a period of 6 months.
For several years, the Chinese herbal combination PC-SPES underwent significant investigation as a treatment for prostate cancer, with apparently impressive results. However, subsequent investigation revealed that PC-SPES contained undisclosed pharmaceutical ingredients (principally, a form of estrogen and the strong blood thinner Coumadin), and that these were probably responsible for its benefits.
Other Uses for Traditional Chinese Herbal Medicine
A large, double-blind study conducted in China reported that use of the traditional remedy xue-zhi-kang by people with a previous history of a heart attack
In a small, double-blind, placebo-controlled trial, use of the herbal combination Banxia Houpo Tang (also called Hange Koboku-To or Magnolia and Pinelliae Formula) was tested for the treatment of impaired cough reflex in people who had suffered a
Various Chinese herbal formulas have been evaluated for the treatment of
respiratory infections. The results of published studies appear to indicate that these formulas are more effective than standard antibiotics, but the poor design of most of these trials precludes placing much faith in their outcomes.
A double-blind study performed in Hong Kong evaluated the potential benefits in
One study evaluated the effectiveness of an herbal combination containing herbs commonly used for the treatment of
Numerous studies have evaluated traditional Chinese herbal medicine for treatment of liver cancer with generally positive results.
A double-blind, placebo-controlled study of 29 people with
The Kampo remedies Saiko-keishi-to and Shosaiko-to have been suggested for the treatment of
Other traditional herbal combinations with some supporting evidence (often from studies of questionable quality) include Xiao-Yao-San (Free and Easy Wanderer) for
In one study, the herbal formula Duhuo Jisheng Wan, widely used for
One double-blind, placebo-controlled study tested the remedy Hochu-ekki-to for enhancing immune response to influenza vaccine, but failed to find benefit.
How to Choose a Practitioner of Traditional Chinese Herbal Medicine
There is no general certification for the practice of TCHM. Many people who are certified in acupuncture
There are several serious safety concerns with the use of TCHM.
One concern involves the use of multiple herbs typical in this approach. In general, conventional medicine makes a point of using as few medications as possible (in theory, at least) because the greater the number of medications, the greater the risk of harm. (Also, when medications are used together and harm does result, it’s hard to know which drug was at fault.) From this perspective, formulas consisting of 5, 10, or 30 herbs are quite worrisome.
Interestingly, such combinations are actually designed for the purpose of reducing risks. According to TCHM theory, the various herbs in a formula balance and moderate each other. Unfortunately, this theory has never been put to the test, and there are reasons not to trust it. Simply put, it is very difficult to get an accurate picture of the risks of a treatment if you don’t keep systematic records of adverse effects, and the ancient Chinese government had no such system in place. In any case, the individualized nature of treatment would make it almost impossible to track harm. Herbalists would be expected to notice immediate, dramatic reactions to herbal formulas, and one can assume with some confidence that treatments used for thousands of years are at least unlikely to cause such problems in very many people who take them. However, certain types of harm could be expected to easily elude the detection of traditional herbalists. These include safety problems that are delayed, occur relatively rarely, or are difficult to detect without scientific instruments. How would a traditional herbalist ever know, for example, if a treatment caused liver failure in one out of 100,000 people who used it, especially if such failure took 2 or more years to develop? If such a death did occur in the herbalist’s patient population, it would probably be attributed to hepatitis or some other common cause.
These factors may explain why Chinese herbal medicine traditionally uses treatments that are now recognized as potentially dangerous, such as mercury, arsenic, lead, licorice, coltsfoot, and Aristolochia.
Mercury, arsenic, and lead accumulate slowly in the body, and for many years their harm can only be detected by lab tests. Licorice (used in many herb formulas to “harmonize” the ingredients) can raise blood pressure and disturb blood chemistry. 33,34
Other reported complications of Chinese herbal treatments include movement disorders and ovarian failure.
Another set of potential problems arises from the fact that Chinese herbal medicine does not restrict itself to plant products with subtle effects. Many traditional Chinese herbal remedies are, simply put, poisons. When taken in proper doses, they may be safe for use, but dosage miscalculation or use in a particularly susceptible person may lead to serious consequences, including death. For example, in Hong Kong, poisoning caused by the herb aconite (used in numerous Chinese herbal formulas) was sufficiently widespread that public health authorities felt it necessary to launch an information campaign to combat the problem.
Besides toxicity caused by Chinese herbs, other problems have been caused by adulteration of herbal products with unlisted ingredients.
In another episode, 8 out of 11 Chinese herbal creams sold in the United Kingdom for the treatment of eczema were found to contain strong pharmaceutical steroids.
Herbal products approved by the Japanese government have undergone meaningful safety testing and are very unlikely to contain known toxins or unlisted drugs. However, this does not mean they are completely safe. For example, several case reports suggest that therapy for chronic hepatitis combining an approved herbal formula with the standard drug interferon can cause severe inflammation of the lungs.
The herbal formulas Takeda Kampo Ichoyaku K-matsu, Taisho Kampo Ichoyaku, and Kanebo Kampo Ichoyaku Hused, all used to treat upset stomach, might reduce the effectiveness of the Parkinson's disease medication
The bottom line: TCHM is a potentially dangerous form of treatment that should only be used under the supervision of a physician.
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Last reviewed May 2008 by EBSCO CAM Review Board
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