Critical analysis of Echinacea preparations marketed in Germany

Naunyn Schmiedebergs Arch Pharmacol. 2024 Nov 28. doi: 10.1007/s00210-024-03634-2. Online ahead of print.

Abstract

Colds are the most common cause of incapacity to work in 2023 and therefore have a significant impact on the German economy. Echinacea preparations are considered a non-specific immune stimulant that is used as a phytotherapeutic agent for the treatment and prevention of colds. In the 2021 ZEIT ranking of the best-selling pharmacy-only medicines in Germany, four Echinacea preparations were among the top ten, and they experienced a new hype during the SARS-CoV-2 pandemic. In this study, 22 Echinacea monopreparations, which are approved as herbal medicinal products, were analyzed based on their package inserts. The preparations used in clinical studies were compared with the preparations available on the market with regard to the criteria of plant species used, plant part used, preparation (extract or pressed juice), drug-extract ratio, single dose administered, standardization of the preparations, prior performance of an ingredient analysis, galenics, dosage, duration of administration, and daily dose administered. The analysis revealed that the preparations available on the market are very heterogeneous. The composition can vary considerably in terms of ingredients. For customers, these products appear homogeneous in terms of their presentation on the market. The legal framework conditions promote this situation. The clinical studies are also unable to adequately reflect the market situation. New studies based on market reality, with an analysis of ingredients in the preparations used, a standardized study design, and the inclusion of hematological and biochemical parameters in the evaluation should improve this situation. Days of incapacity for work as an outcome parameter could be well suited.

Keywords: E. pallida; E. purpurea; Echinacea; Echinacea extract; Echinacea pressed juice; Alkamides; Chicory acid; Common cold; Polysaccharides; Standardization.