Vaccine / Specialty Immunization

Fluzone High-Dose Quadrivalent (influenza vaccine, quadrivalent, high dose)

Sanofi · High-Dose Inactivated Influenza Vaccine

FDA Approved 2019 Intramuscular (IM) injection Specialty Medication
Fluzone High-Dose Quadrivalent 2026-2027 formula box and prefilled syringe

What is Fluzone High-Dose Quadrivalent? Fluzone High-Dose Quadrivalent is an inactivated influenza vaccine by Sanofi containing 180 mcg of hemagglutinin (HA) per 0.5 mL dose — four times the antigen of standard-dose vaccines. It is specifically indicated for adults 65 years and older.

About Fluzone High-Dose Quadrivalent

Brand NameFluzone High-Dose Quadrivalent
Generic / INNinfluenza vaccine, quadrivalent, high dose
Drug ClassHigh-Dose Inactivated Influenza Vaccine
ManufacturerSanofi
AdministrationIntramuscular (IM) injection
FDA Approval2019
📦 0.5 mL single-dose prefilled syringe; 180 mcg HA (4 x 45 mcg HA) per 0.5 mL

FDA-Approved Uses for Fluzone High-Dose Quadrivalent

Indications are based on FDA approval. Your healthcare provider determines appropriate use based on your specific diagnosis, stage, biomarker status, and overall clinical picture.

  • Prevention of influenza in adults 65 years of age and older
  • Quadrivalent formula covers two influenza A and two influenza B strains per season

How Does Fluzone High-Dose Quadrivalent Work?

Fluzone High-Dose Quadrivalent is an egg-based inactivated influenza vaccine that contains 45 mcg HA per strain (180 mcg total) — four times the antigen content of standard-dose (15 mcg/strain) flu vaccines. Higher antigen content is intended to produce a stronger immune response in older adults whose immune systems may respond less robustly to standard vaccines.

Dosage & Administration

0.5 mL intramuscular injection, once annually. For adults 65 years and older only. Timing follows current ACIP recommendations (typically late summer to fall before flu season).

⚠️ Important

Dosing is individualized by the prescribing clinician. Never adjust your dose without consulting your healthcare provider. This information is educational only and does not replace the official prescribing information.

Warnings, Precautions & Side Effects

General Warning

Not for use in children or adults under 65. Allergic reactions including anaphylaxis may occur. Do not administer to patients with history of severe allergic reaction to any influenza vaccine component. Syncope may occur post-injection.

⛔ Serious Warnings & Precautions
  • Severe allergic reaction / anaphylaxis
  • Syncope
  • Guillain-Barré syndrome (rare association)

Common Side Effects

  • Injection site pain
  • Headache
  • Myalgia
  • Malaise
  • Injection site erythema
  • Low-grade fever

This is not a complete list. Always report new or worsening symptoms to your healthcare provider promptly.

Storage & Handling

Refrigerate at 2°C to 8°C (36°F to 46°F). Do not freeze. Use before expiration date.

BiologicHealthPlus provides temperature-monitored cold-chain specialty delivery for medications requiring refrigeration. Never use a medication if its storage conditions have been compromised.

Insurance Coverage, Prior Authorization & Patient Assistance

🛡️ Commercial Insurance

Fluzone High-Dose Quadrivalent is covered by most major commercial insurance plans when medically necessary and prior authorized. Coverage tier and cost-sharing vary by plan.

✅ Prior Authorization

Prior authorization is required by virtually all insurance plans for Fluzone High-Dose Quadrivalent. BiologicHealthPlus handles the complete prior authorization process at no cost to patients or providers.

🏥 Medicare Coverage

Medicare Part D covers this oral specialty medication. Medicaid coverage varies by state.

🆓 Patient Assistance

Manufacturer patient assistance programs may be available for eligible uninsured or underinsured patients. Contact BiologicHealthPlus for a confidential eligibility review.

Prior Authorization Patient Assistance Insurance & Savings Medication Costs

Frequently Asked Questions — Fluzone High-Dose Quadrivalent

Fluzone High-Dose Quadrivalent is a high-antigen inactivated influenza vaccine by Sanofi, containing 180 mcg HA per dose — four times the standard dose. It is indicated specifically for adults 65 and older, who often need a stronger immune stimulus.

As people age, the immune system becomes less responsive to vaccines — a process called immunosenescence. Higher-antigen vaccines like Fluzone High-Dose are designed to overcome this by providing a stronger antigenic stimulus.

Fluzone High-Dose is manufactured using egg-based technology. People with severe (anaphylactic) egg allergies should consult their healthcare provider. A recombinant alternative like Flublok Quadrivalent may be considered.

Fluzone High-Dose Quadrivalent is covered under Medicare Part B for adults 65+ as a preventive vaccine benefit, generally with no cost-sharing when received from a participating provider.

Related Medications

Flublok Quadrivalent  ·  Fluad Quadrivalent (adjuvanted)  ·  Standard-dose quadrivalent flu vaccines

Related Conditions

Influenza prevention in older adults  ·  Seniors 65+  ·  Immunosenescence

Comparisons

Flublok Quadrivalent

Authoritative References

Medical Disclaimer: This page is for general educational purposes only and does not constitute medical advice, diagnosis, or treatment. Always consult your oncologist, hematologist, or licensed healthcare professional before making any treatment decisions. Last reviewed: August 2026 by the BiologicHealthPlus Clinical Team.