Oseltamivir is an antiviral medication used to treat influenza A and influenza B (flu), and to prevent flu after exposure. The medication is taken orally. The Infectious Disease Society of America, the United States' Centers for Disease Control and Prevention (CDC), and the United Kingdom's National Institute for Health and Care Excellence recommend the use of oseltamavir for people who have complications or are at high risk for complications who present within 48 hours of first symptoms of infection. They recommend its use to prevent infection in at-risk people but not the general population. The CDC recommends that clinicians use their discretion to treat those at lower risk who present within 48 hours of first symptoms of infection.
Oseltamivir phosphate (GS 4104) is a neuraminidase inhibitor recommended for the treatment and prophylaxis of influenza A and B.