Purified polysaccharides prepared from Echinacea possess a strong activating force on the body's macrophage-mediated defense system. These macrophages initiate the destruction of pathogens and cancer cells. Echinacea activates macrophages by itself, independent of any effect with T-cells.

A tumor-inhibiting principle has been found, a oncolytic lipid-soluble hydrocarbon from the essential oil. The echinacosides glycosides appear to be the primary `antibiotics', but there are many other active substances present which probably function synergistically. The polysaccharides possess the best immune stimulating properties and are also antiviral. Other constituents have been shown to possess good anti-tumor, bacteriostatic, and anesthetic activity.

This all points to the conclusion that its actions relate to immune system functioning on some level, helping deal with infections and stimulating the immune response. It activates the macrophages that destroy both cancerous cells and pathogens, increases the level of phagocytosis by raising levels of white blood cells such as the neutrophils, monocytes, eosinophils, and B lymphocytes. It also has an effect on properidin levels, indication an activation of the complement system.