Kampo, Japan's unique herbal medicine tradition, is one form of Tradi-tional East Asian or Oriental Medicine derived from ancient China. Kampo consists of 148 government-regulated, ancient, multi-herb pharmaceutical preparations taught to many medical students* and prescribed by the major-ity of practicing Japanese physicians. These prescriptions by traditionally conservative physicians-such as obstetricians, pediatricians, and orthopedic surgeons-include herbal formulas with such ingredients as ephedra (Ephedra sinica, Ephedraceae), aconite (Aconitum napellus, Ranunculaceae) root, and licorice (Glycyrrhiza glabra, Fabaceae) root.
*The study of Kampo is not compulsory.
Unlike the United States, where most herbal preparations are regulated as dietary supplements (technically foods, not drugs), herbal medicines in Japan are regulated as pharmaceutical preparations. Both the industry and the government conduct exten-sive monitoring of agricultural and manufacturing processes as well as post-marketing surveillance to guarantee the safety of
these preparations. Furthermore, access to Kampo herbal medicines is guaranteed as part of Japan's national health plan for each of its citizens. In the West, however, Kampo still remains a secret to all but a few.
Kampo, like the traditional medicines of modern China, Vietnam, and Korea, has roots that extend back to ancient China's Han Dynasty (200 BCE to 220 CE). The term Kampo itself incorporates 2 characters: 漢(kan) for the Han dynasty and 方(po) denoting "way" or "method." Thus, Kampo means "the way of the Han Dynasty." Although Kampo has developed within Japan's borders and within Japan's culture over the past 1400 years, only recently have Kampo practitioners expressed interest in sharing Kampo's unique insights with the world. The US Food and Drug Administration (FDA) has approved 4 Kampo formulas as Investigational New Drugs (INDs) for formal clinical trials: Saireito (approved in 1990), Shosaikoto (1994), Keishibukuryogan (2004), and Daikenchuto (2005), with the latter two having been approved under the FDA's recent, more stringent criteria. Several university-based clinical trials are now underway in the United States. Recent HerbalGram articles have addressed 2 specific Kampo herbal formulas, Shosaikoto for liver diseases and Juzentaihoto for cancer.1,2 The purpose of this article is to provide a brief introduction to the history and philosophy of Kampo as currently practiced in Japan. This will include descriptions of the herbs and formulas used, diagnostic techniques employed, differences from other forms of traditional Asian medicine, and the government safety regulations followed.
Kampo Components and Practices
Many herbs used in Kampo are already familiar to American herbalists. Examples include spices such as cinnamon (Cinnamomum cassia, Lauraceae; and C. spp.), garden plants such as rhubarb (Rheum palmatum, Polygonaceae), and herbs containing alkaloids used in over-the-counter (OTC) medicines, such as ephedra (although such OTC drugs contain either the synthetic alkaloids ephedrine or pseudoephedrine, not a natural chemically-complex extract of the herb). However, the "how and why" of their use in Japanese Kampo practice may be unique. For example, cinnamon is used as a warming agent, rhubarb (Rheum officinale, Polygonaceae) root is used as a cooling agent, and ephedra is used to elicit sweating. Each is used as one component of a multi-herb formula in a set ratio with presumed synergy. For instance, the addition of cinnamon to ephedra significantly enhances ephedra's anti-tussive and diaphoretic properties.
In North America, echinacea (Echinacea spp., Asteraceae) is frequently used as an herbal remedy to prevent or treat symptoms of the common cold or upper respiratory illness. However, in Japan, as many as 20 different Kampo multi-herb formulas are prescribed with precision for colds and flu syndromes. The choice of agent is dictated by the patient's constitutional state-termed the sho (correlated to the term zheng in the differential diagnosis employed in traditional Chinese medicine)-which is determined from the patient's history and a physical exam, in conjunction with the stage of the illness.
Determining the patient's sho is quite important for a Kampo diagnosis. New categories of thought used for assessing a patient include 4 basic categories: yin and yang, hypofunction or hyperfunction (body energy), hot or cold (heat energy), and interior or exterior (location of symptoms). Physicians also refer to 6 stages of illness, which correspond to observable changes over time in illnesses. Three states are characterized as yang (febrile, relatively external and active) and 3 states are considered yin (cold, internal, and passive).
The patient's state of illness and overall sho, as diagnosed by a clinician, determine the type of Kampo treatment prescribed. For instance, a fatigued patient with poor digestion who presents with acute onset of chills, headache, nasal congestion, and moist skin would typically be prescribed keishito (cinnamon decoction) for his or her tai yang stage of illness. Keishito, one of Kampo's most important base formulas, consists of cinnamon (keihi) bark, peony (Paeonia spp., Paeoniaceae) root, jujube fruit (Ziziphus jujuba, Rhamnaceae), licorice, and ginger (Zingiber officinale, Zingiberaceae). This combination is the foundation for multiple other Kampo formulas. However, should the patient with the same cold have a stronger constitution and no perspiration, differ-ent formulas would be used for the same tai yang stage of disease. Either maoto (ephedra decoction) or kakkonto (kudzu decoction) would be appropriate based on the constellation of additional symptoms. Maoto consists of ephedra, apricot kernel (Prunus armeniaca, Rosaceae), cinnamon, and licorice. Kakkonto consists of the base formula keishito with the addition of 3 more herbs: kudzu (Pueraria lobata, Fabaceae) root, cinnamon, and ephedra.
Kampo practitioners gather information through 4 exams: boushin (visual examination of the patient's face, nails, and tongue), bunshin (use of the sense of smell and hearing), monshin (questioning regarding physical state including bowel and blad-der function as well as physical sensations such as coldness), and sesshin (physical examination of the pulse and abdomen). Key to this approach is the emphasis on use of the senses rather than on quantified measurements such as blood pressure, tempera-ture, heart rate, etc. While the latter biomedical measurements are employed in modern Kampo practice, Kampo practitioners clearly prioritize observational "sense" data over objective, quanti-fiable data. Likewise, Kampo practitioners emphasize the subjec-tive, qualitative, and intuitive aspects of the patient's presenta-tion. In this fashion, Kampo practitioners practice true patient-centered care.
Unique to traditional Asian medicine traditions is the exami-nation of the tongue and of the pulse. Both exams provide important information about the constitutional state of the body. However, especially unique to Kampo is the prioritization of the abdominal exam. Fukushin is the term used to describe the unique abdominal diagnosis by palpation found in Kampo. For each region of the abdomen, temperature, peristaltic move-ment, aortic pulsation, tenderness, muscular tone, and resistance to pressure are assessed. Kampo practitioners also assess for a "splashing" sound in the epigastric region. These assessments are not found in conventional Western medicine. Their results are crucial for prescribing the correct Kampo formula. For example, Keishito is often appropriate for patients with bilateral rectus muscle tension. Ninjinto (ginseng decoction, made from the roots of Panax ginseng, Araliaceae) is appropriate for patients with succession sounds due to stagnant stomach fluid. And bupleurum (Bupleurum falcatum, Apiaceae-saiko in Japaenese) root-based formulas are highly appropriate for patients with kyokyokuman, substernal resistance to palpation.
Kampo's Shared Roots with Other Asian Medicine Traditions
Kampo, like other forms of Traditional Asian Medicine, is based upon classical Han Dynasty texts and their associated ways of diagnosing and treating illness. These texts arrived in Japan via Korea beginning in the 6th century CE. International exchange of such texts continued until the end of the 9th century. Chinese medical textbooks imported during this period include the 2 clas-sic texts authored by the famous physician Zhang Zhong Jing: the Shokanron (傷寒論, Shang Han Lun in Chinese; Treatise on Cold Damage in English) and the Kinki-Yoryaku (金匱要略, Jinkui Yaolue in Chinese; Essential Prescriptions from the Golden Coffer in English). The oldest extant herbal medicine text in Japan, the Ishimpo (医心方, roughly translated as The Core Approach of Medi-cal Practice), dates from the year 984. These 30 volumes were compiled by Yasuyori Tanba using imported texts.
The Separate Development of Kampo
During Japan's Kamakura (1192-1333), Nanbokucho (1334-1391), Muromachi (1392-1573) and Azuchimomoyama (1574-1603) periods, Japanese medicine was influenced strongly by Buddhist monks and others educated in Song and Ming China.� During the 16th century in Japan, the influential Goseihoha school (後世方派, "Future Way School") developed, which sought to incorporate herbal medicine, moxa and acupuncture into one therapeutic approach. This was led by the Japanese physician Dosan Manase, author of the famous text the Keitekishu (警笛集) (1574). This book's content was derived from medical texts of the Song, Jin-Yuan, and Ming-era Chinese texts, as well as from the author's personal experiences. Manase's book empha-sized simplicity and practicality, ideas which served as the foun-dation for Kampo's unique development.
During the Edo (Shogun) (1604 to 1868), under the government policy termed kaikin 海禁"maritime restrictions") or sakoku (鎖国"lock up of country"), Japan's borders were closed to all but a very limited amount of contact with Dutch East Indies Company employees on man-made Dejima Island in Nagasaki Bay. On penalty of death, Japanese citizens could not leave the country and foreigners could not enter the country. After 1641, all international connections were extremely limited; this included even neighboring Chinese who were officially limited to Dejima Island. Unofficial trade did exist but came with great risk as it was not approved by the government. At Dejima, Japan first learned of Western science and of internal human anatomy via physicians who shared their Dutch medical and anatomical texts.�
During this time of national seclusion, Kampo further devel-oped into its uniquely Japanese approach. The kohoha classicist school ( 古方派) proclaimed the motto "return to the Shang Han Lun" (Shang Han Lun is the Chinese term for the book noted previously, Shokanron in Japanese) but, in fact, it downplayed or rejected abstract concepts such as yin and yang as well as the doctrine of the 5 elements (fire, earth, metal, water, wood). This school did, however, emphasize the Shang Han Lun's 6 stages of illness, which were previously described.
From this school and the famous physician Yoshimasu Todo (1702-1773) came the important principles of sho (証) ("consti-tutional state of the body") as well as ki-ketsu-sui (気血水) (qi, blood, water). The patient's sho became the guide for proper prescribing. Moreover, the clinician was taught to look for signs of pathologic change in qi, blood, or water balance. Ki-ketsu-sui is Kampo's theory of pathologic mechanisms and their treatments. Additionally, Dr. Yoshimasu established the unique Japanese diagnostic approach of abdominal palpation for assessment of one's sho (証) and thus determination of the appropriate herbal formula.
The confluence of multiple schools of thought led Kampo teachers and apprentices to incorporate new medical theories and practices and develop compromise schools of thought (i.e., setchuha and kanransetchuha). These included, to varying degrees, knowledge of Western medicine, including human anatomy. This confluence appears to be where Kampo devel-oped its very pragmatic, empirical approach. Those elements incorporated into the new schools of thought included anything found to be helpful, no matter what the source. Thus, heavy dependence on esoteric philosophy was de-prioritized in favor of methods of treatment established by practical experience. Notable texts from the end of the Shogun era include 2 that are frequently consulted today: the Futsugo Yakushitsu Hokan and the Futsugo Yakushitsu Hokankuketsu by Sohaku Asada.
After Japan's civil war in 1868, the Shogunate government was replaced and the imperial family returned to power in what is termed the Meiji Restoration. During the Meiji era (1868-1912), Japan overtly rejected traditional cultural elements, including Kampo, and encouraged their replacement with Western equivalents, including Western medicine. For more than 100 years, the government openly suppressed traditional herbal medicine and promoted Western medicine. This govern-mental policy supported advances in surgery and immuniza-tion as well as in pharmaceutical research, which led to the isolation of the alkaloid ephedrine from the Kampo herb mao (Ephedra sinica), by Nagayoshi Nagai in 1887.
This active suppression changed in 1976 when Toru Takemi, MD, the powerful president of the Japanese Medical Associa-tion, successfully led legislative efforts to incorporate Kampo into the national formulary. As a result, today 148 ancient, multi-herb formulas are included for reimbursement under the guaranteed universal healthcare coverage by the Japanese government. Annual sales of Kampo formulas now total more than one billion US dollars.
Kampo Today
Kampo differs from other Traditional East Asian Medicines, including those of Taiwan, Korea, Vietnam, Classical China and the People's Republic of China (PRC), by its focus on an empirically-verified, standardized approach that de-prioritizes classical philosophical theory, emphasizes the importance of abdominal diagnosis, and standardizes both doses and formu-las.
Every licensed physician in Japan can practice and prescribe Kampo herbal medicines if he or she wishes. In fact, more than 70% of surveyed physicians from a 2003 report claimed to prescribe Kampo.3 However, few physicians train using classical texts. For many physicians who prescribe Kampo frequently, such as orthopedic surgeons, general surgeons, and gynecologists, only a few formulas are necessary to know and prescribe for the needs of their respective specialties. Knowl-edge of pulse diagnosis and 5 element theory is not believed necessary for the benefit of patients. However, knowledge of both tongue and abdominal diagnosis is quite important for recognizing a patient's sho (証) and for determining the correct prescription.
Kampo formulas in Japan are typically prescribed at set doses and set ratios of the multi-herb ingredients. These doses tend to be much smaller than doses used in China. The actual herb species utilized may differ as well. Occasionally, the doses prescribed in Japan can be supplemented with the addition of small amounts of single herbs such as bushi (附子) (Aconitum spp.) or yokuinin (coix seed, Coix lacrymaa-jobi, Poaceae).
Unlike the many thousands of herbal formulas currently in use in China, Japan's Kampo tradition focuses on the 148 formulas covered by the national health insurance plan. Rarely are formulas used outside of this group. One example of an additional Kampo formula sometimes prescribed in Japan but not included in the 148 government-covered formulas is ifuto for inflammatory bowel disease. This formula is a set dose, set ratio 8-herb formula that would be used based on empiri-cal experience as well as abdominal exam/sho diagnosis. This would be prepared by prescription using fresh herbs at special pharmacies in Japan.
Overwhelmingly, the primary for a physician's limited efficacy of Western medicines. Physicians consulted for the 2003 survey3 noted that the availability of Kampo greatly expands the range of treatment options for non-specific patient concerns. The 5 most common reasons for prescribing Kampo are, in descend-ing order: autonomic imbalance (including menopausal symp-toms), constipation, acute upper respiratory illnesses, cramps, and allergic rhinitis. The 10 most commonly prescribed formu-las are found in Table 1.
Kampo Safety
Kampo medicines are pharmaceutical-grade prescription drugs. The Kampo Medicine Manufacturing Association meets or exceeds governmental Good Manufacturing Practice (GMP) standards for each of the 148 formulas. This includes extensive testing for confirmation of proper species identity, as well as testing for microbial, heavy metal, or pesticide contam-ination. Each formula is standardized using at least 2 marker compounds. And, most importantly, extensive post-marketing safety surveillance is conducted by the government with the participation of the prescribing physicians. This has confirmed the safety for formulas containing such ingredients as ephedra, aconite, and licorice. For identified safety issues, such as interstitial pneumonitis from use of interferon agents with Shosaikoto, the Japanese government has required publication of black box or red box warnings for physicians and patients.
Innovative Research
There is a heavy emphasis on basic science in Japan that extends from conventional Western medicine to also include research on Kampo. Human subject research is exceedingly rare in Japan. For Kampo, although some clinical trials exist, randomized, placebo controlled trials that meet Consolidated Standards of Reporting Trials (CONSORT) standards for quality have yet to be conducted. (The CONSORT standards, which are endorsed by leading medical journals and profes-sional societies, identify information considered essential in the reporting of two-group parallel randomized, controlled trials.4)
In Japan, historical experience guides physicians' prescrib-ing practices. Thus, university-based Kampo research is geared toward deepening the understanding of the mechanisms of action. As noted in the recent HerbalGram review of Juzentai-hoto,2 extensive pre-clinical research has been conducted on clinically-useful Kampo formulas in the past 30 years. Some-how this treasure trove of pre-clinical data, including data on the treatment of cancer, has been largely overlooked by the West. Such data, however, has been incredibly helpful for the recent rapid IND approval of 4 Kampo formulas by the US FDA. (Such IND approval merely indicates that the herbal formulation can be subjected to human clinical trials and is not an acknowledgement by the FDA of the product's purported activity or benefits, although it does presume the formula's consistency and relative safety.)
Innovative Kampo research today includes analysis of the intestinal metabolism of herbs and the subsequent changes in host gene expression. Such research calls upon gene chip and protein chip technologies as well as systems biology thinking to understand the complex mechanisms of action inherent in multi-herb, multi-receptor targeting agents. Use of 3-dimen-sional high performance liquid chromatography with advanced mathematical modeling supports standardization of Kampo interventions for clinical trials. There is adequate reason to believe that such research will lead to enhancements in the health of aging populations and in preventing the onset of disease. Exciting results are being published this year on ulcer, influenza and multiple sclerosis treatments.
Conclusion
Today, Kampo is gaining greater attention and recogni-tion within the West. Even after the opening of Japan's sealed borders in the late 1860s, Japan's medical system has had relatively limited openness to inquiries and evaluation by the West. Today, however, there is increasing interest and open-ness among Kampo practitioners to sharing insights from Kampo with professionals and markets in the West. This represents a remarkable new opportunity to understand in a deeper sense human illness, herbal properties, and herbal medi-cines. Through Kampo's unique perspective, herbalists can enrich their understanding of commonly used herbs. Herbal researchers can appreciate the many decades of solid pre-clini-cal research conducted on standardized formulas. Patients can appreciate the prioritization of their subjective experience. And everyone can appreciate the emphasis on safety found in Kampo prescription medicines. As stated in an ancient Japanese proverb, 温故知新(on ko chi shin): "Revisiting past wisdom leads to new knowledge."
Gregory A. Plotnikoff, MD, MTS, FACP, an internist and pediatrician, is the medical director of Allina Health Care's Insti-tute for Health and Healing in Minneapolis, Minnesota. From 2002 to 2007, he served as a visiting associate professor in the Center for Kampo Medicine at Keio University School of Medicine in Tokyo, Japan.
Kenji Watanabe, MD, PhD, FACP, an internist with a doctor-ate in immunology and post-doctorate training in genetics, is the director of the Center for Kampo Medicine at Keio University School of Medicine in Tokyo, Japan.
Fumiko Yashiro is a junior double-majoring in Biology and Studio Art at Carleton College in Northfield, Minnesota.
Recommended Resources
Japanese Society of Oriental Medicine. Introduction to Kampo: Traditional Japanese Medicine. Elsevier, Tokyo. 2005.
Keio University School of Medicine Department of Kampo Medicine Web site. Available at:
http://web.sc.itc.keio.ac.jp/kampo/english/index.html.
References
- 1. Wen J. Sho-saiko-to, a clinically documented herbal preparation for treating chronic liver disease. HerbalGram. 2007;73:34-43.