Baloxavir is used for the treatment of uncomplicated influenza in patients aged 12 years and older. It works by inhibiting the cap-dependent endonuclease activity of the influenza virus, which stops viral replication early in the infection process. The drug is effective against both influenza A and B viruses. It is typically administered as a single oral dose, offering a convenient alternative to multi-day antiviral regimens. Baloxavir has also been studied for post-exposure prevention of influenza in household contacts and has shown effectiveness in reducing the risk of developing symptomatic flu after exposure. Its rapid action helps reduce the duration of symptoms, viral load, and may lower transmission risk when given early in infection.