Quality assessment of herbal preparations as a precondition of pharmacological and clinical studies.

In order to give guidelines for the characterization and standardization of plant material used for pharmacological, clinical and toxicological studies, suggestions are made how to handle extracts or preparations in which the active principles are known, extracts or preparations in which the active principles are unknown, and mixed (multi) preparations containing several raw drugs or extracts. For each category, practical examples of analytical methods are mentioned mainly based on HPLC fingerprint analysis.