Amantadine (1-Adamantanamine) is an orally avtive and potent antiviral agent with activity against influenza A viruses. Amantadine inhibits several ion channels such as NMDA and M2, and also inhibits Coronavirus ion channels. Amantadine also has anti-orthopoxvirus and anticancer activity. Amantadine can be used for Parkinson's disease, postoperative cognitive dysfunction (POCD) and COVID-19 research.