Rapid Immune Response* (formerly RX-A Defense)® supports the body’s rapid response to immune stressors.* Made with Supercritical extracts of two species of Echinacea root, this formula contains high levels of Alkylamides – constituents effective in supporting a quick immune response.* With Elderberry, Ginger and Andrographis included, Rapid Immune Response* (formerly RX-A Defense)® is a complete immune support formula.*