Oseltamivir (Tamiflu®) and zanamivir (Relenza®) are relatively new drugs. Oseltamivir is a prodrug of a selective inhibitor of neuraminidase, an enzyme and glycoprotein at the surface of influenza virus.
Neuraminidase stimulates the penetration of the virus and facilitates the release of newly formed viruses. Oseltamivir thus causes viral aggregation at the cell surface and reduces viral replication. The drug is registered for the prevention and treatment of influenza A and B virus infections. Oseltamivir is generally well-tolerated.
Zanamivir is an effective drug against both influenza A and B viruses.
Extra info: In contrast to amantidine, zanamivir can be used in both influenza A and B infections.
Zanamivir is given orally or parenterally.
Extra info: Zanamivir is administered by inhalation.