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Which antiviral drugs were used to treat H1N1 infection in 2009?

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Caring for flu victims — influenza pandemic (H1N1) of 2009 Doctors at the Mexico City Navy Hospital wearing protective gear as they tend to patients complaining of H1N1 flu-like symptoms.

During the 2009 H1N1 influenza pandemic, the primary antiviral drugs used for treatment were oseltamivir (Tamiflu) and zanamivir (Relenza). These medications belong to a class of drugs known as neuraminidase inhibitors, which function by preventing the release of the virus from infected cells, thereby slowing the spread of the infection within the body.123

Because some H1N1 viruses showed evidence of developing resistance to oseltamivir, which was typically the first-line treatment, alternative options were utilized for specific cases. In October 2009, an intravenous antiviral drug called peramivir was granted emergency-use authorization by the U.S. Food and Drug Administration. This treatment was reserved for hospitalized patients who had not responded to oral or inhaled antivirals or who were suffering from life-threatening illness.1