Kampo medicine (漢方医学, Kampō igaku) is a traditional herbal medical system that originated in ancient China and was introduced to Japan around the 5th century (see History of Kampo Medicine ). Over the centuries, it evolved uniquely within Japan, becoming an integral part of the nation’s traditional healing culture. Today, Kampo medicine is integrated with modern Western medical practice and is covered under Japan’s national health insurance system.
The term Kampo medicines (漢方薬, Kampōyaku) refers to pharmaceutical preparations made from natural ingredients and prescribed according to the theories of Kampo medicine. Unlike Western medicine, which tends to use single chemical substances, Kampo formulas typically combine multiple herbs based on traditional medical principles to create prescriptions known as Kampo formulas (漢方処方, Kampo shoho). Each formula contains a blend of various crude drugs, which may include roots, bark, leaves, seeds, or minerals. Depending on the method of preparation, these formulas can take forms such as decoctions (湯剤, tozai), powders (散剤, sanzai), pills (丸剤, ganzai), or external preparations.
In modern times, extract formulations (漢方エキス製剤, Kampo ekisu seizai) have become widely used, as they allow for easier preparation and administration compared to traditional decoctions. These extracts are produced by boiling crude drugs to draw out their active components, then concentrating and drying the liquid into granules or powders.
Even though extract formulations are widely used in clinical settings today, there are still pharmacies in Japan that prepare Kampo medicines in the traditional way — a practice that many patients deeply appreciate and continue to prefer.
1) Decoction
This traditional method involves boiling dried herbs in water to produce a warm, drinkable decoction. The amount of water and boiling time vary depending on the formula and desired strength. Decoctions are prepared fresh each day and represent the most traditional form of Kampo medicine.
2) Powders and Pills
To prevent the loss of active ingredients during boiling, some Kampo medicines are prepared as powders or pills. Powders are made by mixing ground herbs, while pills combine these powders with binding agents such as honey and are shaped into small balls.
3) Extract Formulations
Extract formulations are made by boiling Kampo prescriptions, concentrating the liquid, and drying it into granules or powder. They are easy to use, store, and have become the most common form of Kampo medicine today. Available in various types—such as granules, tablets, and syrups—they are designed for modern clinical convenience.
4) Ointments
External applications are relatively few, with Shiunko (紫雲膏, “Purple Cloud Ointment”) being a well-known example. These ointments are mainly used to treat skin problems, wounds, and inflammation.
The Role of Kampo Medicine in Modern Japanese Healthcare
Kampo therapy is not only a part of Japan’s traditional culture but also an essential component of modern medical practice. Under Japan’s national health insurance system, only licensed physicians are authorized to diagnose and prescribe Kampo medicines, while pharmacists and other registered healthcare professionals support their preparation, dispensing, and patient guidance.
Because of growing patient demand for Kampo medicine, more physicians are now integrating Kampo treatments into modern scientific practice, applying their medical expertise to ensure safe and effective use. To support this integration, Kampo medicine education grounded in traditional Kampo theory has been included in all medical school curricula across Japan since 2007.
While Kampo medicines offer many therapeutic benefits, they also carry potential risks such as side effects or adverse outcomes resulting from incorrect Kampo diagnoses. To prevent such issues, medical supervision is essential during treatment, and Kampo therapies should be provided under the care of healthcare practitioners properly trained in Kampo medicine.
