The fastest way for viruses to attack the body is through the mucous membrane that sits in the nose - at least for the viruses that cause colds and flu. Viruseptin contains the active substance iota-carrageenan (Carragelose), which envelops the virus particles and prevents them from sticking in the mouth and throat, while moisturizing the mucous membranes, which helps the body's natural defenses against cold viruses.