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Pharmacology of antiviral drugs for influenza

Kimon C Zachary, MD
Section Editors
Martin S Hirsch, MD
Morven S Edwards, MD
Deputy Editor
Anna R Thorner, MD


Two classes of antiviral drugs are available for the prevention and treatment of influenza:

The neuraminidase inhibitors, zanamivir, oseltamivir, and peramivir, which are active against both influenza A and influenza B.

The adamantanes, amantadine and rimantadine, which are only active against influenza A. Due to a marked increase in resistant isolates, these agents should not be used in the United States for influenza prophylaxis or treatment except in selected circumstances, which are discussed separately. (See "Prevention of seasonal influenza with antiviral drugs in adults", section on 'Choice of antiviral drug' and "Treatment of seasonal influenza in adults", section on 'Choice of antiviral drug'.)

Zanamivir and oseltamivir are the first-line agents for the prophylaxis and treatment of influenza. Peramivir can be used for the treatment of influenza in patients who cannot receive zanamivir or oseltamivir (eg, those who cannot tolerate inhaled or enteral agents).

The pharmacologic issues related to these drugs will be reviewed here. Their role in the prevention and treatment of influenza are discussed separately. (See "Prevention of seasonal influenza with antiviral drugs in adults" and "Treatment of seasonal influenza in adults" and "Seasonal influenza in children: Prevention and treatment with antiviral drugs" and "Treatment and prevention of pandemic H1N1 influenza ('swine influenza')" and "Treatment and prevention of avian influenza".)

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Literature review current through: Nov 2017. | This topic last updated: Aug 20, 2016.
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