Antiviral Drugs for Seasonal Influenza: Additional Links and Resources

(Current for the 2012-2013 Influenza Season)

Current Antiviral Treatment Recommendations are available.

Neuraminidase Inhibitors

The majority of currently circulating influenza viruses are susceptible to the neuraminidase inhibitor antiviral medications oseltamivir and zanamivir; however, rare sporadic cases of oseltamivir resistant 2009 influenza A (H1N1) and A (H3N2) viruses have been detected worldwide in recent years. Antiviral treatment with oseltamivir or zanamivir is recommended as early as possible for patients with confirmed or suspected influenza who have severe, complicated, or progressive illness; who require hospitalization; or who are at greater risk for influenza-related complications.

• Oseltamivir (brand name Tamiflu® [505 KB, 28 pages]) is approved for treatment of influenza in persons aged two weeks and older, and for chemoprophylaxis to prevent influenza in people one year of age and older.
• Zanamivir (brand name Relenza®) is approved to treat flu in people 7 years and older and to prevent influenza in people 5 years and older.

Adamantanes

In recent years, widespread adamantane resistance among influenza A (H3N2) virus strains has made this class of medications less useful clinically. In addition, circulating 2009 H1N1 virus strains are resistant to adamantanes. Therefore, amantadine and rimantadine are not recommended for antiviral treatment or chemoprophylaxis of currently circulating influenza A virus strains. (These medications are active against influenza A viruses but not influenza B viruses.)

• Amantadine (generic) is approved to treat and prevent only influenza A viruses in people older than 1 year.
• Rimantadine (Flumadine®, generic) is approved to prevent only influenza A virus infection among people older than 1 year. It is approved to treat only influenza A virus infections in people 17 and older.

The CDC’s weekly FluView provides the latest information on antiviral drug resistant isolates collected via routine surveillance in the United States.

Find labels and label updates for approved drug products at Drugs@FDA.