FLUBLOK® QUADRIVALENT and FLUZONE® HIGH-DOSE QUADRIVALENT are indicated for immunization against disease caused by influenza A and B strains contained in the vaccine. FLUBLOK® QUADRIVALENT is given to people 18 years of age and older. FLUZONE® HIGH-DOSE QUADRIVALENT is given to people 65 years of age or older.

Flu and its complications could be lurking anywhere.

The flu is more dangerous than you may think.

Flu-related complications can put older adults at a greater risk for hospitalization, pneumonia, or heart attack.

Fight the flu with higher-dose flu vaccines from Sanofi. They’re proven to provide better flu protection than standard-dose flu shots in older adults. They’ve even been shown to better protect against flu-related complications.

See the studies page for full study design of our randomized controlled trials and real-world evidence.

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Did you know?

In a study of almost 1,300 people 40 years or older, some people were approximately 10 times more likely to experience their first heart attack after having the flu.

Not all flu vaccines are the same.

You do have a choice, so ask for a Sanofi higher-dose flu vaccine by name.
Get the vaccine for your age.

For adults 65+


  • The #1 used flu vaccine for people 65 and older*
  • Superior flu protection for adults 65 and older versus standard-dose FLUZONE® (INFLUENZA VACCINE)
  • In a clinical study conducted in 2011-2012 and 2012-2013 in approximately 32,000 adults 65+, the trivalent formulation proved to be 24% more effective at preventing the flu than standard-dose FLUZONE® (INFLUENZA VACCINE)
  • The efficacy of the trivalent and quadrivalent formulations of FLUZONE HIGH-DOSE (INFLUENZA VACCINE) are related because both are made using the same process and have overlapping compositions.
  • Formulated specifically for adults 65+, with 4X the dose of a standard-dose flu shot
  • Compared to FLUZONE®, the most common side effects were slightly more frequent and included pain and redness at the injection site, muscle ache, tiredness, and headache
  • The immune response and side effects of FLUZONE® HIGH-DOSE QUADRIVALENT were similar to the trivalent formulation in a 2017-2018 clinical study in 2,670 adults 65+. FLUZONE® HIGH-DOSE QUADRIVALENT is expected to provide better protection against the flu compared with standard-dose quadrivalent flu vaccines


Internal calculations by Sanofi based on IQVIA database of total flu vaccines administered from 8/22-4/23 in people 65+. Study details and information maintained by Sanofi.

For adults 18+


  • Has 3 times the standard-dose flu shot
  • In a clinical study of approximately 8,600 people (~4,300 in each of 2 groups), FLUBLOK® QUADRIVALENT was proven to be 30% more effective at preventing flu in people 50+ than FLUARIX® QUADRIVALENT
  • Made with recombinant technology
  • Egg-free and preservative-free
  • 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
A wolf in sheep's clothing

Find your Sanofi flu shot.