Inflammation and Native American medicine: the role of botanicals.

There is a growing interest in medicinal botanicals as part of complementary medicine in the United States. In particular, both physicians and consumers are becoming aware of the use of herbals by Native American societies; many botanicals sold today as dietary supplements in the United States were used by Native Americans for similar purposes. Yet, these supplements represent only a small number of the >2500 different plant species from vascular taxa, and >2800 species from all taxa, known to have been prized for their medicinal properties by the indigenous inhabitants of the North American continent. We review some of the studies of the immunomodulatory activities of botanicals used by native peoples of North America, the bioactive constituents responsible for those activities, and the mechanisms by which these constituents might modulate the immune system. We focus particularly on 3 species of purple coneflower (ECHINACEA:) because of the widespread use of purple coneflower in the United States to boost immunity and prevent upper respiratory infections. Seven of the 10 most common botanicals sold in the United States were used extensively by Native Americans. However, there are very few data to support such use and even less information about drug toxicity or interactions.