How do flu

antivirals

work?

Antiviral flu medications help you recover by fighting the influenza virus in your body.1

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How do antivirals work to treat the flu?

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

By treating the flu in this way, an antiviral could help you to feel better sooner than if you didn’t take one.4

It’s important that you talk to your doctor within 48 hours of noticing your first symptoms of the flu so that treatment can be as effective as possible.7

Why 48 hours?

Over-the-counter flu
antiviral vs. medications or antibiotics

  • Antivirals
    • Require a prescription
    • Treat the flu virus directly4
    • Can reduce the flu’s ability to replilcate4
    • Can avoid potentially serious complications5,7
  • Over-the-counter medicines
    • No prescription needed
    • Treats symptoms rather than the flu itself8
    • No effect on the flu’s ability to replicate
    • No effect on complications9
  • Antibiotics
    • Usually require a prescription
    • Treat bacteria, so no effect on the flu,10 unless there is a complication and your doctor deems this necessary
    • No effect on the flu’s ability to replicate
    • Effective against bacterial complications10,11
Antivirals
Over-the-counter medicinesAntibiotics
Require a prescription
No prescription needed
Usually require a prescription
Treat the flu virus directly4
Treats symptoms rather than the flu itself8
Treat bacteria, so no effect on the flu,10 unless there is a complication and your doctor deems this necessary
Can reduce the flu’s ability to replicate4
No effect on the flu’s ability to replicate
No effect on the flu’s ability to replicate
Can avoid potentially serious complications5,7
No effect on complications9
Effective against bacterial complications10,11

And

what about

antibiotics?

tissue

Antibiotics are not the same as antivirals. Antibiotics are used to fight bacterial infections.1 Because the flu is caused by a virus and not a bacteria, antibiotics cannot target the source of the flu and will not help people get better.10

Antibiotics will not help ease your symptoms either.10 In fact, using antibiotics when they are not needed can do more harm than good. This is because bacteria can start building resistance to the antibiotic, which can weaken the antibiotic response to any future bacterial infections.1,2

So if you suspect you have the flu, remember that antibiotics will not have any effect.

Discover more about some of the common misconceptions related to the treatment of the flu with our online tool:

Fact or Fiction

Learn more
doctor

Think you’ve got the flu? Call or 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 health care provider as soon as possible.

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

References

  1. Centers for Disease Control and Prevention. What You Should Know About Influenza (Flu) Antiviral Drugs: Fact Sheet, 2016. Available from: https://www.cdc.gov/flu/pdf/freeresources/updated/antiviral-factsheet-updated.pdf. Last accessed: November 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. Lehnert R et al. Dtsch Arztebl Int 2016; 113(47): 799–807.
  8. Centers for Disease Control and Prevention. Symptom relief, 2018. Available from: https://www.cdc.gov/antibiotic-use/community/for-patients/symptom-relief.html. Last accessed: November 2018.
  9. Klepser M. Drugs 2014; 74(13): 1467-1479.
  10. Low D. Clin Microbiol Infect 2008; 14(4): 298–306.
  11. Bonten M. BMJ 2006; 332(7536): 248-249.
  12. World Health Organization. Antibiotic resistance. Available from: http://www.who.int/news-room/fact-sheets/detail/antibiotic-resistance. Last accessed: November 2018. 

References

  1. Centers for Disease Control and Prevention. What You Should Know About Influenza (Flu) Antiviral Drugs: Fact Sheet, 2016. Available from: https://www.cdc.gov/flu/pdf/freeresources/updated/antiviral-factsheet-updated.pdf. Last accessed: November 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. Lehnert R et al. Dtsch Arztebl Int 2016; 113(47): 799–807.
  8. Centers for Disease Control and Prevention. Symptom relief, 2018. Available from: https://www.cdc.gov/antibiotic-use/community/for-patients/symptom-relief.html. Last accessed: November 2018.
  9. Klepser M. Drugs 2014; 74(13): 1467-1479.
  10. Low D. Clin Microbiol Infect 2008; 14(4): 298–306.
  11. Bonten M. BMJ 2006; 332(7536): 248-249.
  12. World Health Organization. Antibiotic resistance. Available from: http://www.who.int/news-room/fact-sheets/detail/antibiotic-resistance. Last accessed: November 2018.