Antiviral medications are a class of drugs typically used to prevent or shorten the severity and duration of a viral infection such as influenza. Those used for the flu are considered a second line of defense against infection (with the seasonal flu vaccine being the first). Antivirals are most effective if taken soon after flu exposure or flu symptoms appear, but they are generally reserved for severe cases and those who are at-high risk for flu-related complications, as well as those who regularly interact with them (such as caretakers).

There are four antiviral medications currently approved by the U.S. Food and Drug Administration (FDA) to treat the flu in the United States:

Rapivab (peramivir)
Relenza (zanamivir)
Tamiflu (oseltamivir phosphate)
Xofluza (baloxavir marboxil)1
Two other medications, amantadine and rimantadine, have been shown to target influenza A viruses. However, they are not recommended to prevent or treat influenza at this time as the flu viruses that make people sick are resistant to these drugs.

how the flu is treated
Hilary Allison / Verywell
Benefits
Antiviral medications can reduce your fever and symptoms of influenza. They have the best chance of success if you start treatment within two days of experiencing symptoms, and they can speed up your recovery by about one day.

Antiviral medications can also lessen the risk of complications including childhood ear infections, respiratory issues such as pneumonia, and potential hospitalization for adult patients.

For those at a higher risk of serious flu complications, receiving early antiviral treatment can lessen the chance of becoming severely ill and requiring a hospital visit. Research has even shown that early antiviral treatment can reduce someone's risk of death from the flu.2

Antiviral drugs help reduce the amount of virus being produced within the body of the infected person. That can help limit the spread of the virus to others.

How Germs Are Transmitted
How They Work
Three of the antiviral drugs used for influenza are neuraminidase inhibitors. Neuraminidase is a glycoprotein found in the influenza virus.

After the virus infects a human cell, its genetic material (RNA) orders the cell to make more viral copies. These bud to the surface of the host cell, where the viral neuraminidase must cleave the bond to sialic acid (found on the surface of the host cell) in order for the new viruses to be released.

Tamiflu (oseltamivir phosphate), Relenza (zanamivir), and Rapivab (peramivir) block the active sites of neuraminidase and, therefore, help prevent the new viruses from being released and going out to infect more cells.3п»ї The peak of this viral replication is at 24 to 48 hours after infection. So, in order to stop release of more virus, the drug needs buy effexor 75mg to be administered as soon as possible. These drugs work against both influenza A and influenza B viruses.4п»ї

Xofluza (baloxavir marboxil) is a cap-dependent endonuclease inhibitor. Rather than preventing the release of viral particles, it interferes with viral RNA transcription so the virus can't replicate inside the host cells. It is also effective against both influenza A and influenza B.4п»ї

As viruses change year after year, they can develop resistance to these antiviral drugs. As a result, researchers are continually looking for new drugs with slightly different methods of action that might be effective.5п»ї Reserving antiviral drugs for those most at risk, rather than giving them to anyone, is thought to help slow the development of viral resistance to these drugs.

Who Should Take Them
Antiviral medications are available by prescription only. They are not routinely given to every person who has a mild case of influenza but are reserved for those who have the most severe illness, are at high risk of complications, or close contacts of those at high risk. As well, they may be given to prevent influenza in a person who is at high risk of complications or their close contacts.

In All Cases
Here are the scenarios in which antiviral treatment should always be started, regardless of whether or not you have had the flu vaccine:6

You are hospitalized with influenza.
You have severe or progressive flu illness but are not hospitalized.
You have the flu and are 65 years or older, pregnant, or have given birth in the past two weeks. Children with the flu who are age 2 or younger should also receive an antiviral.
Groups at higher risk include people with chronic diseases such as asthma or lung disease, and those with weakened immune systems.
Groups at Higher Risk for Flu Complications
Possible Use
Your healthcare provider can consider prescribing antiviral medications in these instances where you are having flu symptoms, regardless of having been immunized or being in a high-risk group:6

You have developed flu symptoms in the past 48 hours.
You have flu symptoms and you live with people who are at high risk of developing flu complications.
You are having flu symptoms and you are work in a healthcare setting where you have contact with how to purchase keflex 250 mg people who are at high risk of developing flu complications.


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