Good clinical practice and phytotherapy

The GCP Guideline of the European Community on the performance of clinical trials became obligatory in June 1991. As the GCP standards have mainly been set for innovative drugs, there is a certain danger that these criteria could not be fulfilled by medicines used in phytotherapy. As regards, the chances and risks of the European guideline, especially for herbal medicines, the differences between chemically-defined and herbal drugs, as well as the extent, to which herbal medicines might be concerned by the guideline, have to be taken into account. Herbal medicines are different from chemically defined medicines in their character as well as in their medicinal use. They always contain a mixture of numerous substances. Data on preclinical investigations are often incomplete, whereas, on the other hand, physicians and patients have a long-term experience in applying these medicines. They are, in general, well-tolerated and therefore suitable for the treatment of chronic diseases. Due to a characteristic taste and smell, the production of placebos is often impossible. The GCP directive also contains basic elements concerning chemically defined drugs as well as herbal medicines in a similar way.