What is phytotherapy ?
phytotherapy, the use of plant-derived medications in the treatment and prevention of disease. Phytotherapy is a science-based medical practice and thus is distinguished from other, more traditional approaches, such as medical herbalism, which relies on an empirical appreciation of medicinal herbs and which is often linked to traditional knowledge. An herbalist’s approach generally has not been evaluated in controlled clinical trials or in rigorous biomedical studies, whereas numerous trials and pharmacological studies of specific phytotherapeutic preparations exist. The interpretation and acceptance of such evidence for phytotherapeutic practices varies. In some countries, it is considered sufficient to license phytotherapeutic products as medicines, whereas in other countries, phytotherapy is viewed as a form of traditional medicine.
There are a number of phytotherapeutic preparations in use. Examples include preparations derived from the leaves of ginkgo (Ginkgo biloba), which are used to treat a range of minor cognitive disorders and certain other disorders of the central nervous system; the aerial parts of St. John’s wort (St. Johnswort; Hypericum perforatum), which typically are used in the treatment of mild to moderate forms of depression; the aerial parts and roots of Echinacea angustifolia (and other species of Echinacea), which are used in the treatment and prevention of the common cold and other respiratory conditions; and parts of African devil’s claw (Harpagophytum procumbens), the root of which is used to treat chronic lower back pain.
A commonly used but often poorly defined concept in phytotherapy is standardization, which is the requirement of having a minimum amount of one or several active compounds or groups of compounds in the plant extract. Often a range from a minimum to a maximum amount is given. In the field of phytotherapy, standardization applies only to extracts and by definition only to those where the active constituents are fully characterized. For example, an extract containing a certain percentage of compound class X (e.g., flavonoids) must contain one specific compound of the group (e.g., the flavonoid rutin). The quantification often is carried out by using chromatography-based techniques (e.g., gas chromatography or high-performance liquid chromatography), capillary electrophoresis, atomic absorption spectroscopy, or mass spectrometry.
Phytotherapy and national health care systems
The practice of phytotherapy differs widely throughout the world. In some countries, such as South Korea and Japan, proven phytotherapy products are integrated into health insurance coverage. Other countries, including China, India, and Nepal, offer wide health care coverage for herbal medicines, which fall under traditional medicine services. In most other parts of the world, however, such products are not integrated into health care or health insurance programs. They are, rather, much more a patient’s private choice, and they often are sold as over-the-counter (OTC) products, though these products may be recommended or prescribed by a wide range of health care practitioners, including general practitioners and naturopathic doctors.
Since phytotherapy is a system of medical practice that is based on scientific or medical evidence, its products are pharmacologically active medicines, similar to conventional pharmaceutical drugs. Thus, phytotherapy cannot be subsumed under complementary and alternative medicine (CAM), which generally is linked to different philosophical principles.