Echinacea products vary in their composition, due to the use of different species, plant parts, extraction methods, and addition of other components (Planta Med 2008;74:633-7). Some preparations are based on the stabilized fresh juice of aerial parts of E. purpurea, and are rich in hydrophilic derivatives such as polysaccharides and glycoproteins. Other echinacea products come from an extract of root material and contain more lipophilic compounds including N-alkylamides (Ann Intern Med 2010;153:769-777).