Diagnosis: Viral Infection: oseltamivir
• Antiviral therapy for influenza includes neuraminidase inhibitors (i.e., oseltamivir and zanamivir) and amantadine and rimantadine. Neuraminidase inhibitors act directly on the viral proteins, decreasing the virulence of infection.
• Oseltamivir and zanamivir are effective against both influenza A and B. Therapy should be started within 48 hours of symptoms for optimal effectiveness.
• Amantadine is active against influenza A virus and has little or no activity against influenza B virus. The emergence of resistant influenza A strains has limited the utility of this agent.
• Rimantadine inhibits viral replication of influenza A virus H1N1, H2N2, and H3N2 by blocking uncoating of influenza A. The emergence of resistant influenza A strains has limited the utility of this agent.
• Antiviral agents are not currently available for respiratory viral pathogens other than influenza.
