Nowadays Echinacea is world widely used and one of the most important medicinal herb for the treatment of upper respiratory tract infections, owing its anti-viral, anti-inflammatory and immunomodulatory properties. However, various Echinacea preparations tested in clinical trials differ greatly. There is some evidence that preparations based on the aerial parts of Echinacea purpurea might be effective for the early treatment of colds in adults, but results are not fully consistent. Beneficial effects of long lasting administration of high Echinacea doses, for preventative purposes, have not been shown in rigorous randomized trials.