In spite of the great advances of modern scientific medicine, traditional medicine is still the primary form of treating disease for the majority of people in developing countries, including China. Even among those to whom Western medicine is available, the number of people using one form or another of complementary or alternative medicine is rapidly increasing worldwide.
With its abundant botanical resources, China has been a pioneer in treating human diseases with medicinal herbs. The medicinal use of herbs in China by tradition has been attributed to a legendary emperor, Shen Nong (3494 BC), who tasted and tested plants and discovered their medicinal properties.
The recorded use of plants for medicinal purposes in China dates back to 2800 BC.
The most comprehensive classic herbal encyclopedia, Ben Cao Gang Mu, a description of formulas or prescriptions to treat human diseases, was published in the 16th century by Dr. Li Shizhen (1517-1593 AD). This original materia medica recorded over 350 crude drugs; since then a great number of drugs and prescriptions have been added. In 1958, the year of the Great Leap Forward, Chairman Mao declared that Traditional Chinese Medicine (TCM) was a vast treasure chest and challenged the Chinese people to validate its efficacy and to combine the best elements of Traditional Chinese Medicine TCM with modern Western medicine to improve the nation’s health-care delivery system.
In 1999, Hong Kong’s Chief Executive, Tong Chee-Hwa, announced his intention to develop Hong Kong as a world center for TCM.on the specific beneficial effects of Chinese herbal medicine. Some herbs commonly used in Chinese medicine have been studied and chemical constituents that could represent the therapeutic actions of the herbs have been identified.
However, numerous mechanisms are likely involved in the various actions of a single herbal medicine. Elucidation of these mechanisms will provide the scientific basis for establishing the efficacy and safety not only of Chinese herbal medicine, but all forms of medicinal herbs. In China, herbal medicines in the ancient tradition continue to be widely used. These medicines commonly contain ten or more herbs, thereby making it difficult to determine the pharmacological effects of individual drugs incorporated in prescriptions. In modern Western medicine, the use of a single chemical component is preferred in order to avoid drug interactions. In Chinese medical philosophy, therapeutic value and efficiency are increased by combining various herbs and ingredients in one prescription to treat a single disease. A compound prescription often consists of four different functional groups and each group usually comprises more than one herb. The “principal” provides the principal curative effect; the “adjuvant” helps strengthen the principal effect; the “auxiliary” relieves secondary symptoms or decreases the toxicity of the principal and the “conductant” directs the action of the principal to the target organ or site. There are several logical explanations for the philosophy of mixing several crude extracts to achieve greater benefits. First, crude drugs given in combination may act synergistically. Second, the combination may have unknown interactions that might diminish possible adverse side effects of one or more of the components. Third, the combination may prevent the gradual decline in effectiveness observed when single drugs are given over long periods of time. Chinese herbal medicine generally uses either the whole plant or crude extracts as medicines, which tend to include a wide range of chemical constituents. Neither the whole plant nor crude extracts deliver highly concentrated medicines. By contrast, conventional Western prescription drugs usually contain a single-molecule active ingredient to treat a single ailment. This practice is more likely to cause side effects than the gentler and less concentrated phytochemicals in traditional herbal medicines.
In recent scientific investigations conducted in China, active ingredients have been isolated from herbal preparations. Many studies have focused on the effects of active ingredients both in vivo and in vitro, and on providing pharmacological data compatible with the modern scientific view. However, it has been suggested that the quality of trials needs substantial improvement in order to promote evidence-based decision-making, and frequently it has not been determined whether actions of isolated compounds shown in vitro or in animal studies would be relevant to the doses of herbal medication used in clinical practice. More systematic analysis and testing of Chinese herbs are needed for the development of a standard set of therapeutic agents that may be administered with reliable efficacy and good quality control. In order for Chinese herbal medicine to be accepted as reliable alternative medicine, the safety of medicinal herbs and their efficacy for the treatment of specific diseases must be demonstrated. A first step is establishing reliable sourcesof ingredients.