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Coming down with the flu is likely to mean spending several days in bed feeling lousy. But the flu can be far more serious. So far, this season’s flu is responsible for between 140,000 and 250,000 hospitalizations—and 54 deaths in children alone, according to the Centers for Disease Control and Prevention. (See the CDC flu activity map, below.)
If you get the flu, your doctor can prescribe an antiviral medication, such as oseltamivir (Tamiflu and generic), that can help get you back on your feet a bit faster. But antivirals can have side effects, and not everyone with the flu needs one. Here, answers to pressing questions about these drugs.
What Are Antivirals, Anyway?
Tamiflu is the best-known of the prescription flu antivirals—drugs that can ease symptoms and shorten the course of the illness by inhibiting the growth of the flu virus in the body.
For those who may need an antiviral (more on that below), the CDC is recommending one of four for use this flu season: Tamiflu and its generic (in pill or liquid form), baloxavir (Xofluza, in pill form), zanamivir (Relenza, an inhaled powder), and the IV drug peramivir (Rapivab, which is reserved for very sick, already hospitalized flu sufferers).
Both Tamiflu and its generic and Relenza are usually prescribed for five days, while the newer Xofluza is taken in a single dose of two pills. One dose of Rapivab is given via an IV for 15 to 30 minutes.
It’s important to know that these drugs are not a type of antibiotic. Antibiotics are used to fight bacterial infections and are ineffective for viral infections, including the flu.
How Effective Are Antivirals?
A 2014 Cochrane review found that when given within 48 hours of the onset of flu symptoms—such as fever, cough, sore throat, body aches, and chills—oseltamivir lessens a person’s sick time by about 17 hours in adults and 29 hours in children.
There may be some benefit in taking antivirals even outside of that 48-hour window. One 2013 CDC study published in The Lancet Infectious Diseases found that children given oseltamivir within five days of getting sick experienced an improvement in symptoms.
They also had significantly less virus shedding, which means they were much less likely to spread the illness to others.
Who Should Take Tamiflu?
If you’re in good health and come down with the flu, you don’t necessarily need Tamiflu or another antiviral medication, because you’ll most likely get better on your own within one to two weeks using self-care strategies, such as resting, getting plenty of fluids, and taking over-the-counter pain relievers for fever, headache, and muscle aches.
“By the time most people drag themselves out of bed to see the doctor, they’re on the road to recovery already,” says Nicole Bouvier, M.D., an infectious disease specialist at the Icahn School of Medicine at Mount Sinai in New York City.
Many experts, including those at the CDC, say that people at high risk for flu complications, however, should take an antiviral medication. This includes people older than 65, kids 5 and younger—especially those younger than 2—pregnant women and those up to two weeks postpartum, and people who live in nursing homes. Find the entire list here. (Note that because Relenza is inhaled, it shouldn’t be taken by anyone with asthma or chronic obstructive pulmonary disease.)
Some research suggests that taking an antiviral can help reduce the likelihood that flu will become severe enough to require hospitalization or lead to death. But the evidence “is not crystal clear about the prevention of those serious complications,” says Michael Hochman, M.D., M.P.H., director of the Gehr Family Center for Health Systems Science and Innovation at the Keck School of Medicine of USC in Los Angeles.
Still, for people at higher risk of flu complications, the potential protective benefit of an antiviral probably outweighs the risks of side effects (more on those below), Hochman says.
In addition, “if anyone’s sick enough to already need to be in the hospital, and they come down with the flu, they absolutely should be on one,” Bouvier says.
If you have a loved one in a nursing home or an assisted-living facility, he or she should also receive an antiviral if there’s a flu outbreak there, even if he or she isn’t sick.
According to the CDC, if at least two residents get the flu within three days of each other, everyone should get a drug such as Tamiflu for at least two weeks, and continue for at least a week after the last case has been identified.
And if you have elderly or infirm people living with you at home, some evidence suggests that taking an antiviral could help prevent you from spreading flu to them, Hochman says.
Otherwise, for normally healthy people, deciding whether to take an antiviral comes down to whether getting better about a day quicker is more important than the possibility of drug side effects.
What Are the Side Effects of Antivirals?
The most common side effects for Tamiflu and its generic are headache, nausea, and vomiting—but taking the drug with food can minimize stomach discomfort. Diarrhea, fever, nausea, and body aches have been reported for Relenza. Diarrhea can occur with Rapivab and Xofluza.
There have also been rare reports of psychiatric side effects such as delirium and hallucinations with Tamiflu and its generic and Relenza, mostly in children. Let your doctor know right away if you notice anything like this.
How Much Do Antivirals Cost?
The cost to you will vary, depending on your insurance plan. Antivirals can be a bit pricey, although the 2016 introduction of generic Tamiflu has helped.
If you don’t have health insurance or your insurer doesn’t adequately cover Tamiflu, its generic, or Relenza (or doesn’t cover them at all) you may be able to get a coupon online that can help you save.
See How the Flu Spreads Across the U.S.
Below, you’ll find the CDC’s weekly influenza surveillance report. By clicking on the play button, you can see how influenza activity has changed over this flu season. (You can also view these maps for past flu seasons via the season dropdown.)
Interactive courtesy of the Centers for Disease Control and Prevention.
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