Influenza, commonly known as the flu, is a respiratory illness caused by viruses that infect the nose, throat, and sometimes the lungs. While many people recover on their own, new medications are continuously being developed to help manage the illness, especially for those at higher risk of complications. These advancements offer new ways to fight the virus directly and reduce the impact of infection.
The Role of Antiviral Medications for Flu
Antiviral medications for influenza are prescription drugs that target the flu virus itself, rather than just alleviating symptoms like fever or body aches. Unlike over-the-counter remedies, which provide symptomatic relief, antivirals work to stop the virus from replicating in the body. This action can reduce the severity and duration of the illness. Prompt use of these medications is particularly beneficial for individuals at higher risk of developing serious flu-related complications.
They are distinct from antibiotics, which are used to combat bacterial infections, and they are not a substitute for annual flu vaccination.
Current New Antiviral Options
One relatively new antiviral medication approved for influenza treatment is baloxavir marboxil, known by its trade name, Xofluza. This drug was approved by the U.S. Food and Drug Administration (FDA) in October 2018 for individuals aged 12 years and older. It is also approved for children aged 5 years to less than 12 years who do not have chronic medical conditions.
Baloxavir marboxil represents a new class of influenza drugs known as cap-dependent endonuclease inhibitors. Unlike older antivirals that require multiple doses over several days, baloxavir marboxil is typically administered as a single oral dose.
How New Antivirals Combat the Flu
Baloxavir marboxil works by targeting a specific enzyme within the influenza virus called cap-dependent endonuclease. This enzyme is crucial for the virus to replicate its genetic material and produce new viral proteins inside infected cells. The influenza virus uses a process called “cap-snatching” to obtain a primer necessary for synthesizing its messenger RNA (mRNA).
By inhibiting the cap-dependent endonuclease, baloxavir marboxil prevents the virus from performing this “cap-snatching” action. This disruption stops the virus from creating functional mRNA, which means it cannot synthesize the proteins it needs to multiply. This unique mechanism effectively halts the spread of the virus within the body.
Important Considerations for Treatment
For new flu medications to be most effective, they should be taken within 48 hours of the onset of flu symptoms. Early administration helps to significantly reduce the duration of illness and can lessen the risk of complications. These medications are generally recommended for individuals aged 12 years and older, and in some cases, for children aged 5 to 12 years without chronic conditions.
People at higher risk for serious flu complications, such as those with chronic health conditions, pregnant individuals, or very young children, are often prioritized for antiviral treatment. Common side effects reported for baloxavir marboxil include diarrhea and bronchitis. These are prescription medications, and a healthcare provider must be consulted to determine if they are appropriate.