Examples of adulteration of medicinal plants/herbal drugs with toxic herbal drugs demonstrate the need to establish good manufacturing practice for herbal starting materials. The concept of Good Manufacturing Practice for the manufacture, processing, packaging and storage of Active Pharmaceutical Ingredients (APIs) should thus also apply to medicinal plants/herbal drugs.

In the case of herbal drug preparations the production and primary processing of the medicinal plant/herbal drug has a direct influence on the quality of the API. Due to the inherent complexity of naturally grown medicinal plants/herbal drugs and the limited analytical techniques to characterise constituents solely by chemical or biological means, reproducible quality of starting materials of herbal origin requires an adequate quality assurance system for the collection and/or cultivation, harvest and primary processing.

Collection in wild habitats, often in developing countries, presents special problems, especially with regard to confusion with similar plants, environmental damage, lack of control and poorly qualified personnel.

The following "Points to Consider" on good agricultural and collection practice does not fall directly under GMP guidelines in the traditional sense. However, these considerations should be used as a basis for the establishment of such an appropriate quality assurance system.