Thimerosal in Sanofi’s Fluzone Multi-Dose Vials Update

On July 23, 2025, the U.S. Department of Health and Human Services (HHS) officially adopted the Advisory Committee on Immunization Practices (ACIP) recommendation to remove thimerosal—a mercury-based preservative—from all influenza vaccines distributed in the United States.

How Does this Recommendation Relate to the Multi-Dose Vials of Sanofi’s Fluzone?

The multi-dose vials of Sanofi’s Fluzone contain a small amount of thimerosal, and as such, fall under the recommendation to remove thimerosal from all U.S. influenza vaccines.

Considering the recommendation change, Sanofi will NOT ship your MDV Fluzone without confirmation of your original order OR a change to another product selection.

Confirming your order of MDV Fluzone: Those who would like to receive their order of MDV Fluzone to administer this flu season MUST confirm your order by calling Sanofi’s customer service department at 1-800-822-2463.
- Remember: Sanofi will NOT ship any doses of Fluzone multi-dose vials without a confirmation from your office.
Changing your order of MDV Fluzone to a different product: If you have purchased MDV Fluzone and would like to change to a different product selection, please call Sanofi’s customer service department at 1-800-822-2463.
- Should you prefer thimerosal-free prefilled syringes (FPS) of Fluzone* for the coming 2025-2026 season, Sanofi has ample supply to accommodate a modification to your order. (There is an additional cost for the Fluzone in PFS)

In conclusion, the recent HHS adoption of ACIP’s recommendation to eliminate thimerosal from all U.S. influenza vaccines, providers who prebooked Sanofi’s Fluzone multi-dose vials must take action. If you intend to keep your MDV order or switch to a thimerosal-free alternative, please contact Sanofi Customer Service at 1-800-822-2463. No MDV orders will be shipped without confirmation. Be sure to review your options and respond promptly to ensure your flu vaccine supply for the 2025–26 season.