Traditional medicines, particularly herbal medicines, have been increasingly used worldwide during the last two decades. Unfortunately, the number of reports of patients experiencing negative health consequences caused by the use of herbal medicines has also been increasing. Analysis and studies have revealed a variety of reasons for such problems. One of the major causes of reported adverse events is directly linked to the poor quality of herbal medicines, including raw medicinal plant materials. It has therefore been recognized that insufficient attention has been paid to the quality assurance and control of herbal medicines.
By resolution WHA56.31 on traditional medicine, Member States requested WHO "to provide technical support for development of methodology to monitor or ensure product safety, efficiency and quality, preparation of guidelines, and promotion of exchange of information". WHO has developed a series of technical guidelines relating to the quality control of herbal medicines of which these WHO guidelines on good agricultural and collection practices (GACP) for medicinal plants are the latest. The guidelines provide a detailed description of the techniques and measures required for the appropriate cultivation and collection of medicinal plants and for the recording and documentation of necessary data and information during their processing.
Despite such guidelines, there is still considerable disparity between knowledge and implementation. For example, it is a difficult task to train farmers and other relevant persons as producers, handlers and processors of medicinal plant materials. While pharmaceutical and other companies are striving to meet the requirements for the quality control of herbal medicines, they cannot force farmers, producers, handlers and processors to follow good agricultural and collection practices for medicinal plants. The training of farmers and other relevant persons is therefore one of many important measures to be taken to ensure that good agricultural and collection practices are adopted in order that medicinal plant materials of high quality are obtained.
Quality control directly impacts the safety and efficacy of herbal medicinal products. Good agricultural and collection practices for medicinal plants is only the first step in quality assurance, on which the safety and efficacy of herbal medicinal products directly depend upon, and will also play an important role in the protection of natural resources of medicinal plants for sustainable use. Until now, only the European Union and a few countries, such as China and Japan have developed regional and national guidelines for good agricultural and collection practices for medicinal plants.
We believe that more countries will develop their own guidelines for the quality control of medicinal plants based on the guidelines developed by WHO. However, there is still a long way to go before such guidelines are implemented worldwide, and cooperative efforts on the part of national authorities, including health, agricultural, trade and research institutes, and nongovernmental organizations will be needed to enable us to reach our goal.
Dr Xiaorui Zhang
Traditional Medicine (TRM)
Department of Essential Drugs and Medicines Policy (EDM)
World Health Organization