FLUBLOK® QUADRIVALENT is a vaccine indicated for immunization against influenza disease caused by influenza A and B strains contained in the vaccine. It is given to people 18 years and older.

FLUBLOK® QUADRIVALENT—the flu vaccine that is proven to give adults 50+ more protection.
Syringe icon showing 30% more effective flublok® quadrivalent vaccine in adults 50+


  • Is FDA approved for people 18+
  • Has 3x the dose of a standard-dose flu shot
  • In adults 50 years of age and older, the most common side effects were pain and/or tenderness at the injection site, headache, and tiredness

In a clinical study of approximately 9,000 people, FLUBLOK® QUADRIVALENT (Influenza Vaccine) was proven to be 30% more effective at preventing flu in people 50+ vs FLUARIX® QUADRIVALENT (a standard-dose vaccine)

The CDC recommends FLUBLOK® QUADRIVALENT, a higher-dose flu vaccine, for people 65+.


FLUBLOK® QUADRIVALENT, FLUZONE® HIGH-DOSE QUADRIVALENT, or an adjuvanted quadrivalent vaccine are preferentially recommended by the CDC for people 65+ over standard-dose flu shots. If none of these are available, then any other age-appropriate influenza vaccine should be used.

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FLUBLOK® QUADRIVALENT is FREE for almost everyone.

$0 for Medicare Part B

$0 for most Medicare Advantage plans

$0 for most private insurance plans


The information above is available at CMS.gov and is current as of 07/01/2023. This information is provided for informational purposes only and is not a guarantee of coverage. The information is gathered from various resources and is subject to change.

Flu infection poses serious risks at all ages.

Even if you’re a younger adult, you can still suffer from flu-related complications that can come with flu.
Additionally, you run the risk of passing the flu virus on to vulnerable people around you.

Adults with heart disease, diabetes, chronic lung disease (asthma, COPD), and other chronic conditions are at higher risk of developing serious flu-related complications.

FLUBLOK® QUADRIVALENT helps reduce the risk of flu and flu-related complications.

A wolf in sheep's clothing

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