[Pharmaceutical comparability of different therapeutic Echinacea preperations].

Cichoric acid and Dodeca 2E, 4E, 8Z, 10E/Z-tetraenoic acid isobutylamide (alkamides 8, 9) are described as immunomodulating active components of Echinacea. We quantified both substances in 25 Echinacea-containing remedies customary in trade. Concerning both active components, we found highly concentrated remedies as well as remedies without any detectable cichoric acid or alkamides. The concentration of both active components varied extremely depending on the type of remedy (homeopathic mother tincture, pressed juice, tablets, spagyric tincture), on the Echinacea-species (Echinacea angustifolia, Echinacea pallida, Echinacea purpurea) and on the part of the plant (root, herb, whole plant). Moreover, we found large differences between comparable drugs of different manufacturers and between different charges of the same remedy. We recommend that preclinical and clinical studies with Echinacea-containing drugs should always include the quantification of the potentially active components. We are convinced, that in the long term this will help to clarify how the different active components contribute to the immunomodulating effect of Echinacea.