Recently approved antiviral drugs include Tamiflu, Flumadine, Symmetrel, and Relenza. These drugs can be used to both prevent and reduce the duration of fever and other symptoms associated with the flu. As with any drug, these medications can have side effects, and people who are allergic to the drugs or to their ingredients should not take them.
What Are Antiviral Drugs?
Although the flu vaccine is the best flu prevention method, antiviral drugs are also available by prescription. These drugs can be used to both prevent and reduce the duration of fever and other flu symptoms. Specific antiviral drugs include:
How Do They Work?
Flumadine and Symmetral were the first two antiviral drugs approved by the U.S. Food and Drug Administration (FDA). These antiviral drugs act against influenza A viruses, but not against influenza B viruses. These drugs inhibit the activity of the influenza virus M2 protein, which forms a channel in the virus membrane. As a result, the virus cannot replicate (make copies of itself) after it enters a cell.
In 1999, the FDA approved two additional drugs to fight the flu: Relenza (zanamivir) and Tamiflu (oseltamivir), which were the first of a new class of antiviral drugs called neuraminidase inhibitors.
The surfaces of influenza viruses are dotted with neuraminidase proteins. Neuraminidase, an enzyme, breaks the bonds that hold new virus particles to the outside of an infected cell. Once the enzyme breaks these bonds, this sets free new viruses that can infect other cells and spread infection. Neuraminidase inhibitors block the enzyme's activity and prevent new virus particles from being released. This limits the spread of infection.