How do flu antivirals work?
Helping you recover from flu. Fast.

Antiviral flu medications help you recover by fighting the influenza virus in your body.1
How do antivirals work
to treat flu?

When a viral infection occurs, the virus particles start to replicate and spread within the body.2,3 Antiviral medications tackle flu by reducing the virus’s ability to do this.4

By treating flu in this way, an antiviral could help you to feel better sooner than if you didn’t take one, and could also help stop the spread of the virus to other people.5,6

Antiviral flu medications or over-the-counter remedies – what’s the difference?

Medications that you can pick up without a prescription at your local pharmacy (over-the-counter medicines) only treat the symptoms of flu and not the virus itself.7 These can be useful for treating a headache or sore throat but won’t stop flu from spreading.3


An antiviral flu medication, prescribed by your doctor, actively reduces the flu virus’s ability to reproduce.4 This stops it spreading to others and helps avoid complications.1,4–6,8

And what about antibiotics?

Antibiotics are used to fight bacterial infections.1 Because flu is caused by a virus and not a bacterium, antibiotics won’t have any effect.9 So if you suspect you have flu, contact your doctor to ask about antivirals.

Discover more about some of the common misconceptions of flu treatment with our fact vs. fiction tool

Think you’ve got flu? Visit your doctor to discuss if an antiviral flu medication might be right for you

If you get sick this flu season, it’s important to speak to your doctor or healthcare provider as soon as possible.


Find out more about flu in your local area using the CDC influenza map.


  1. Centers for Disease Control and Prevention. What You Should Know About Influenza (Flu) Antiviral Drugs: Fact Sheet, 2016. Available from: Last accessed September 2018.
  2. Bouvier NM & Palese P. Vaccine 2008; 26(Suppl 4): D49–D53.
  3. Breitbart M & Rohwer F. Trends Microbiol 2005; 13(6): 278–284.
  4. Stiver G. CMAJ 2003; 168(1): 49–56.
  5. Tsang TK et al. Trends Microbiol 2016; 24(2): 123–133.
  6. Allen UD et al. Can J Infect Dis Med Microbiol 2006; 17(5): 273–284.
  7. Centers for Disease Control and Prevention. Symptom relief, 2018. Available from: Last accessed September 2018.
  8. Centers for Disease Control and Prevention. Treating Influenza (Flu): Fact Sheet, 2017. Available from: Last accessed September 2018.
  9. Low D. Clin Microbiol Infect 2008; 14(4): 298–306.
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Date of preparation: October 2018

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