Echinacea continues to be a popular herbal product, used primarily for treating and preventing colds and flus. Sales were estimated at $132 million in the US alone in 2009, an increase of 7% over the previous year. Reports of major negative clinical trials have had only a modest and temporary effect on the popularity and sale of this herb, contradicting claims that the utility of such research is to inform consumers.
In the current issue of the Annals of Internal Medicine there is a new study of Echinacea for the treatment of cold symptoms: Echinacea for Treating the Common Cold, A Randomized Trial. I won’t hold out the punchline – the study was completely negative. But let’s put the results of this study into the context of the history of Echinacea and the clinical evidence.
History of Echinacea
Modern proponents of Echinacea frequently cite as support the claim that this plant has been used for centuries by many Native American cultures. This much is well-documented, but what is not clear is what Echinacea was used for. For this there is no clear answer, except that Echinacea was used for 15-20 different and unrelated conditions, from fatigue to snake bites. Let us consider the value of the claim for traditional use of any treatment.