ViraStop contains an exclusive blend of proteases to assist the body in purification.* The immune system can then concentrate its full action on the invasion. ViraStop is not an "immune stimulator", rather a supporter of healthy immune function.* This formula contains a blend of eight proteolytic enzymes. ViraStop is Enzymedica"s premier protease formula. In addition to protease Thera-blendTM enzymes, this superior formula contains nattokinase which breaks down excess fibrin, MucolaseTM that digests excess mucus, catalase which works as a potent antioxidant, and serratiopeptidase for supporting healthy circulation.