Comparing phytopharmaceuticals: the example of St. John's Wort

At present, dosage in phytotherapy often falls victim to an undifferentiated point of view. In the case of St. John's Wort, for example, 900 mg of extract has become the standard dosage; however, no studies have investigated the dose-effect ratio, even though there are numerous indications that smaller amounts, particularly of ethanolic extracts, are sufficient to achieve the desired effect. Moreover, listing extract dosages is of no use unless other identifying characteristics are also specified. If phytopharmaceuticals are to be compared with one another, the scope of consideration cannot be limited to single components. The comparison must be carried out comprehensively.