Used primarily in the prevention and treatment of influenza A virus infections, particularly in seasonal flu outbreaks. It works by inhibiting viral replication, specifically blocking the M2 proton channel of the influenza A virus, which prevents uncoating of the virus inside host cells. Commonly prescribed during flu season for high-risk populations, including elderly individuals and those with weakened immune systems. Also used as a prophylactic in institutional settings like nursing homes during outbreaks. Limited effectiveness against influenza B and many current strains of influenza A due to widespread viral resistance. May be used off-label in some neurological conditions, though this is less common.