Fig. (3b) Mechanism of action of iota-carrageenan as an antiviral for the treatment of a common cold. The long, negatively charged iota-carrageenan molecule attracts and traps the newly released positively charged viruses and prevents them from infecting adjacent nasal epithelial cells. The iota-carrageenan and trapped viruses will be transported by mucociliary clearance to the nasopharynx and then swallowed, and the viruses will be destroyed in the acid environment of the stomach. (-VE means negatively charged).