Traditional Chinese Herbal Medicine Overview

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.

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 placebo group.)

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.

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.

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 astragalus , dong quai , ginger , kudzu ( Pueraria lobata), licorice , lycium , Panax ginseng, and schizandra . For more information on the use of these herbs, see the appropriate individual articles.

Besides herbs, substances that we might consider supplements are utilized in TCHM. These include extract of human placenta, ² glandular extracts, and a variety of minerals.

To establish the effectiveness of a treatment, it must be put through a double-blind, placebo-controlled trial . For this reason, our database is organized around such studies. However, there are a few issues that make it a bit difficult to study TCHM in this way.

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 “open label” trials , however, prove virtually nothing because even phony treatments will appear to cause benefits. (For more information, see Why Does This Database Rely on Double-blind Trials? ) We do not report open label trials here.

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. ³

Chronic Hepatitis

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. ⁴ However, a search of the literature uncovered only one large-scale, double-blind, placebo-controlled study supporting its effectiveness. ⁵ In this 24-week trial, the efficacy of Shosaiko-to was tested in 222 people with chronic active hepatitis using a double-blind, placebo-controlled crossover design. Results showed that use of Shosaiko-to significantly improved liver function measurements compared to placebo. Although these results are promising, an absence of long-term evaluation limits their meaningfulness. (Researchers only followed participants for 3 months.)

Other Chinese herbal remedies have been tested as adjuncts to conventional interferon treatment with promising results. ⁶ However, published trials are of generally poor quality.

Note: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 Safety Issues ).

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. ^{7 8} However, the quality of most of these studies was again quite poor—the results are mixed and overall, the evidence for these remedies remains far too weak to rely upon. Two studies failed to find Chinese herbal treatment helpful for hepatitis C. ⁹

Note:There have been numerous cases of hepatitis and other forms of liver injury causedby Chinese herbs. See Safety Issues for more information.

Liver Cirrhosis

Shosaiko-to, mentioned in the previous section, has also shown some promise for preventing liver cancer and liver fibrosis in people with liver cirrhosis or chronic hepatitis. ¹⁰ However, the evidence remains marginal. For example, in a double-blind, placebo-controlled study, 260 people with cirrhosis were randomly assigned to take Shosaiko-to or placebo, along with conventional treatment. ¹¹ Over 5 years of evaluation, people taking the herb appeared to be less likely to develop cancer or die, but the results just missed the ordinary cutoff for statistical significance . For the subgroup of participants without hepatitis B infection, the benefits werestatistically significant at the usual cutoff point.

Irritable Bowel Syndrome

In a double-blind, placebo-controlled trial, 116 people with irritable bowel syndrome (IBS) were randomly assigned to receive individualized Chinese herbal formulations, a “one-size-fits-all” Chinese herbal formulation, or placebo. ¹² Treatment consisted of 5 capsules 3 times daily, taken for 16 weeks. The results showed that both forms of active treatment were superior to placebo, significantly reducing IBS symptoms. However, the individualized treatment was no more effective than the “generic” treatment. Similar results were seen in another study as well. ¹³

Constipation

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. ¹⁴ The results indicate that the higher-dose group, but not the lower-dose group, experienced statistically significant improvements in constipation compared to placebo.

Allergies

In a double-blind, placebo-controlled trial, 220 people with allergic rhinitis were given either placebo or the Kampo remedy Sho-seiryu-to for a period of 2 weeks. ¹⁵ The results showed that use of the herbal formula significantly relieved all major symptoms of allergic rhinitis compared to placebo. Based on this and other more preliminary studies, Sho-seiryu-to has been approved by the Japanese Health Ministry for the treatment of allergic rhinitis and allergic conjunctivitis.

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. ¹⁶ This combination therapy contains the following herbs:

• Rehmannia glutinosa
• Scutellaria baicalensis
• Polygonatum sibiricum
• Ginkgo biloba
• Epimedium sagittatum
• Psoralea corylifolia
• Schisandra chinensis
• Prunus mume
• Ledebouriella divaricata
• Angelica dahurica
• Astragalus membranaceus

Use of Biminne produced significant improvements in some symptoms of allergic rhinitis, while other symptoms showed a trend toward improvement that was not statistically significant. A follow-up evaluation suggested that the results persisted for a year after treatment was stopped.

Benefits have been seen in small studies of other formulations as well. ¹⁷ However, one study failed to find that use of herbal treatments augmented the effectiveness of acupuncture for allergic rhinitis. ¹⁸

Osteoarthritis

A double-blind, placebo-controlled study of 96 people with osteoarthritis of the knee tested the effectiveness of a mixture of three Chinese herbs ( Clematis mandshurica, Trichosanthes kirilowii, and Prunella vulgaris). ¹⁹ Participants were randomly assigned to placebo group or one of three other groups: 200 mg, 400 mg, or 600 mg of the herbal formula 3 times daily. After 4 weeks of treatment, significant improvement in arthritis symptoms was seen in all three treatment groups compared to placebo. No dose appeared conclusively superior to the others.

Muscle Spasms

The Kampo remedy Shakuyaku-kanzo-to is a combination of peony root and licorice , commonly used for the treatment of muscle spasms in general. In a double-blind, placebo-controlled study, 101 people with liver cirrhosis who also suffered from severe muscular spasms at least twice per week were given either Shakuyaku-kanzo-to or placebo 3 times daily for 2 weeks. ²⁰ (The herb combination is not specifically aimed at liver cirrhosis. However, people with liver cirrhosis often have muscle spasms, so it made sense to try an anti-muscle-spasm formula on them.) The results showed significant reduction in frequency and severity of spasms among the participants using the herb compared to those taking placebo. However, some participants using the herb developed edema (swelling caused by excess fluid) and weight gain. Researchers attributed this side effect to the licorice constituent. (See Safety Issues for risks associated with the use of licorice.)

Menstrual Pain

In a double-blind trial of 40 women complaining of menstrual pain , the Kampo formula Toki-shakuyaku-san was compared to placebo with good results. ²¹ The design of this study was interesting because researchers preselected women who, according to the principles of traditional Chinese medicine, would be expected to respond to this Kampo treatment. Over six menstrual cycles, women using the real herbal formula experienced significantly less menstrual pain compared to those in the placebo group. Benefits took three menstrual cycles to develop.

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. ²²

Diabetes

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 diabetes . ²³ Coptis Formula appeared to significantly enhance the effectiveness of the drug; however, the herbs produced marginal benefits at best when taken alone.

Asthma

The Kampo remedy Saiboku-to has been approved by the Japanese Health Ministry for the treatment of asthma . However, meaningful supporting evidence appears to be limited to one small trial. In this double-blind, placebo-controlled crossover study, 33 people with mild to moderate asthma received Saiboku-to or placebo 3 times daily for 4 weeks. ²⁴ Treatment with the herbal remedy improved symptoms of asthma to a greater extent than placebo. Additional measurements suggested that Saiboku-to works by reducing asthmatic inflammation (technically, eosinophilia)

A Chinese study using a proprietary formulation reported benefits as well. ²⁵

Eczema

A Chinese herbal mixture sold under the name Zemaphyte has shown promise as a treatment for eczema . This formula, based on herbs traditionally used for skin conditions, contains the following:

• Ledebouriella seseloides
• Potentilla chinensis
• Akebia clematidis
• Rehmannia glutinosa
• Paeonia lactiflora
• Lophatherum gracile
• Dictamnus dasycarpus
• Tribulus terrestris
• Glycyrrhiza uralensis
• Schizonepeta tenuifolia

In paired double-blind, placebo-controlled trials carried out by one research group, Zemaphyte produced significantly better effects than placebo for both adults and children. ²⁶ Each study enrolled approximately 40 people and used a crossover design in which all participants received the real treatment and placebo for 8 weeks each. Use of the herb significantly reduced eczema symptoms compared to placebo.

However, a subsequent study of similar design performed by a different research group failed to find significant benefit with Zemaphyte. ²⁷ The reason for this discrepancy is not clear.

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. ²⁸

Tension Headache

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 tension headache compared the application of Tiger Balm to the forehead against placebo ointment, as well as against the drug acetaminophen (Tylenol). ²⁹ The placebo ointment contained mint essence to make it smell similar to Tiger Balm. Real Tiger Balm proved more effective than placebo, and just as effective and more rapid-acting than acetaminophen.

HIV

Chinese herbal therapies have been investigated for the treatment of HIV , but the results have not been very promising. In a 12-week, double-blind, placebo-controlled trial, 30 HIV-infected adults with CD4 counts of 200 to 500 were given a Chinese herbal formula containing 31 herbs. ³⁰ The results hint that use of the herbal combination might have improved various symptoms compared to placebo, but none of the differences were statistically significant. Interestingly, people who believed they were taking the real treatment showed significant benefit regardless of whether they were in the placebo group or the real treatment group.

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. ³¹ The results indicate that use of Chinese herbs did not improve symptoms or objective measurements of HIV severity. In fact, people using the herbs reported moredigestive problems than those given placebo!

Prostate Cancer

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. ³² The treatment has since been withdrawn.

There is no general certification for the practice of TCHM. Many people who are certified in acupuncture , however, have significant training in herbal medicine as well. (In general, 500 hours of specific training is considered necessary.) Some states offer the license of OMD (Doctor of Oriental Medicine); licensed OMDs are generally well versed in TCHM.

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