Used in the treatment and prevention of influenza A and B virus infections. It works by inhibiting viral neuraminidase, an enzyme that helps the virus spread from infected to healthy cells. By blocking this enzyme, the virus is less able to replicate and spread in the respiratory tract. Administered via oral inhalation, it is most effective when started within 48 hours of symptom onset. Commonly prescribed during flu outbreaks or for high-risk patients to reduce symptom duration and severity.