Kampo Medicine

What Kampo is

Kampo is Japan's traditional herbal medicine system. Reviewers describe it as a unique Japanese system derived from traditional Chinese herbal medicine. [1] In Japan it is part of mainstream health care in a way that is unusual elsewhere: Kampo formulas are covered within the national health insurance system, and patients can receive Western and Kampo care in the same medical institution. [1]

Origins and cultural context

Chinese herbal medicine was first introduced into Japan from China in 552 AD, according to a 2020 review, and Japan went through a renaissance of the tradition during the Tokugawa period in the 1700s. [1] After the Meiji Restoration of 1868, the government adopted the German system for official medical education and practice and excluded Kampo as pre-modern. Kampo regained official attention around 1970. [1] A 2011 review reports that Kampo prescriptions have been on the national health insurance drug list since 1971. [2]

How Kampo differs from Traditional Chinese Medicine

Kampo has Chinese roots but is its own Japanese tradition today, so this site treats it separately from TCM. Three differences are documented in the sources we read:

• Standard formulas and extracts. Japan has 148 Kampo formulations (mostly herbal extracts) that can be prescribed within national health insurance. [2] Spray-dried granule extracts have increasingly replaced the traditional decoction, and extract preparations make up to 95 percent of the Japanese Kampo market. [2]
• Quality control. Japan's pharmacopoeia and international good manufacturing practice rules standardize purity and toxicity control for these products. [2]
• Who prescribes. A survey cited in the review found more than 70 percent of Japanese physicians prescribe Kampo drugs. [2] The Japan Society for Oriental Medicine had 8,600 members and 2,600 certified board members, and Kampo education was added to the medical-student core curriculum in 2001. [2]

Core ideas, as traditional frameworks

Traditional Kampo treatment starts from a Kampo diagnosis, which the 2011 review describes as based on history, abdominal examination, and tongue and pulse diagnosis. [2] These are traditional frameworks used by trained clinicians. This site does not provide self-diagnosis tools. A 2020 review also cautions that it is risky to use Kampo or Chinese formulas outside the context of their own diagnostic system. [1]

What research shows

A 2011 review examined 135 clinical studies of Kampo extracts, drawn from an evidence report listing 320 trials from 1986 to 2008. Of these, 106 were randomized controlled trials and 23 were placebo-controlled. Most studies were small: two thirds enrolled fewer than 100 people and the overall quality was low. [2]

The 2011 review adds that trial results can be affected by patient expectation, as shown for acupuncture, and that research designed around fixed diagnoses does not represent traditional Kampo treatment. [2] Results for one formula do not carry over to another.

Safety

Kampo extracts are herbal drugs and can cause serious reactions. A review of adverse events reported to Japan's Ministry of Health, Labor and Welfare, cited in the 2020 pain review, found the most frequent events were liver injury (28.2 percent), lung injury (27.8 percent) and pseudoaldosteronism (21.0 percent), a licorice-related problem of fluid retention, low potassium and high blood pressure. [1] Licorice root (Glycyrrhizae Radix) is in 109 of 148 prescription Kampo extract formulas, so clinicians are advised to watch for it. [1]

If you take a prescription medicine, ask a pharmacist or physician before combining it with any herbal product. NCCIH notes that herbs and medicines can interact in harmful ways. [3] Read medication interactions and liver safety and supplements.

Training, regulation and buying outside Japan

In Japan, Kampo is prescribed within the medical system by physicians, and Kampo is part of medical-student teaching. [2] Products sold online or in other countries may be regulated as supplements instead; the US FDA says it does not approve dietary supplements for safety and effectiveness before they are marketed. [4] Do not assume an imported product matches a Japanese prescription formula.

Who should seek conventional care first

See a clinician first for sudden, severe or worsening symptoms, pregnancy, liver or kidney disease, and for children. Tell all your providers about any herbal product. [5]

Related pages

Compare Traditional Korean Medicine, read about Chinese herbal medicine and see historical use vs clinical evidence.