Dosing & Uses
Dosage Forms & Strengths
IM solution
- 0.5mL/prefilled syringe
Influenza Prophylaxis
Indicated for active immunization against influenza virus subtypes A and B contained in the vaccine for adults aged ≥18 yr
0.5 mL IM x1/season
Dosing Considerations
Contents for 2023-2024 Northern Hemisphere season:
- A/Wisconsin/67/2022 (H1N1)pdm09-like virus (new for 2023-2024)
- A/Darwin/6/2021 (H3N2)-like virus (no change from last season)
- B/Austria/1359417/2021 (B/Victoria lineage)-like virus (no change from last season)
- B/Phuket/3073/2013-like virus (B/Yamagata lineage) (no change from last season)
Egg allergy
- The Advisory Committee on Immunization Practices (ACIP) recommends Flublok Quadrivalent for vaccination of persons with egg allergy of any severity
- Flublok Quadrivalent does not use the influenza virus or chicken eggs in its manufacturing process
<18 years: Safety and efficacy not established
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (1)
- ustekinumab
ustekinumab decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Contraindicated. Prior initiating therapy, patients should receive all age-appropriate immunizations as recommended by current guidelines. Immunosuppressants also increase risk of infection with concomitant live vaccines.
Serious - Use Alternative (7)
- brodalumab
brodalumab, influenza virus vaccine quadrivalent, recombinant. immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug. Prior to initiating brodalumab, complete all age appropriate immunizations. No data are available on the ability of live or inactive vaccines to elicit an immune response in patients being treated with brodalumab.
brodalumab, influenza virus vaccine quadrivalent, recombinant. Other (see comment). Avoid or Use Alternate Drug. Comment: Prior to initiating brodalumab, complete all age appropriate immunizations. No data are available on the ability of live or inactive vaccines to elicit an immune response in patients being treated with brodalumab. - elivaldogene autotemcel
elivaldogene autotemcel, influenza virus vaccine quadrivalent, recombinant. Either decreases effects of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: The safety and effectiveness of vaccination during or following elivaldogene autotemcel treatment have not been studied. Vaccination is not recommended during the 6 weeks preceding myeloablative conditioning, and until hematological recovery following elivaldogene autotemcel treatment. Where feasible, administer childhood vaccinations before myeloablative conditioning. .
- ixekizumab
ixekizumab decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug. Prior to initiating ixekizumab, complete all age appropriate immunizations; non-live vaccinations received during treatment with ixekizumab may not elicit an immune response sufficient to prevent disease.
- ofatumumab SC
ofatumumab SC decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug. Administer all immunizations according to immunization guidelines at least 2 weeks before initiating ofatumumab SC for inactivated vaccines, and whenever possible.
- secukinumab
secukinumab decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug. Prior to initiating secukinumab, complete all age appropriate immunizations; non-live vaccinations received during treatment with secukinumab may not elicit an immune response sufficient to prevent disease.
- siponimod
siponimod decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Avoid or Use Alternate Drug. Pause vaccinations beginning 1 week before initiating siponimod and for 4 weeks after stopping treatment. Coadministration with live attenuated vaccines may increase infection risk.
- teplizumab
teplizumab decreases effects of influenza virus vaccine quadrivalent, recombinant by Other (see comment). Avoid or Use Alternate Drug. Comment: Administer all age-appropriate vaccinations before starting teplizumab. Inactivated or mRNA vaccines are not recommended within 2 weeks before teplizumab treatment, during treatment, or 6 weeks after completion of treatment.
Monitor Closely (50)
- adalimumab
adalimumab decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- alefacept
alefacept decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- anakinra
anakinra decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- antithymocyte globulin equine
antithymocyte globulin equine decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- antithymocyte globulin rabbit
antithymocyte globulin rabbit decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- azathioprine
azathioprine decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- basiliximab
basiliximab decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- belimumab
belimumab decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- budesonide
budesonide decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- canakinumab
canakinumab decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- certolizumab pegol
certolizumab pegol decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- cortisone
cortisone decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- cyclosporine
cyclosporine decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. If possible, complete all age-appropriate vaccinations at least 2 weeks before initiating immunosuppressant therapy. Patients vaccinated <14 days before starting immunosuppressive therapy or during immunosuppressive therapy should be revaccinated at least 3 months after therapy is discontinued if immune competence has been restored. Longer waiting periods may be required for drugs that maintain their immunosuppressive effects for more than 3 months after discontinuation (eg, ocrelizumab). .
- deflazacort
deflazacort decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- dexamethasone
dexamethasone decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- etanercept
etanercept decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- everolimus
everolimus decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- fludrocortisone
fludrocortisone decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- glatiramer
glatiramer decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- golimumab
golimumab decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- hydrocortisone
hydrocortisone decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- ibrutinib
ibrutinib decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Coadministration with immunosuppressant therapy reduced efficacy of the vaccine may occur. If possible, complete all age-appropriate vaccinations at least 2 weeks prior to initiation of immunosuppressant therapy. Patients vaccinated <14 days before initiation or during immunosuppressive therapy should be revaccinated at least 3 months after therapy is discontinued. .
- ifosfamide
ifosfamide decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Coadministration with immunosuppressant therapy reduced efficacy of the vaccine may occur. If possible, complete all age-appropriate vaccinations at least 2 weeks prior to initiation of immunosuppressant therapy. Patients vaccinated <14 days before initiation or during immunosuppressive therapy should be revaccinated at least 3 months after therapy is discontinued. .
- infliximab
infliximab decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- leflunomide
leflunomide decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- lomustine
lomustine decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Coadministration with immunosuppressant therapy reduced efficacy of the vaccine may occur. If possible, complete all age-appropriate vaccinations at least 2 weeks prior to initiation of immunosuppressant therapy. Patients vaccinated <14 days before initiation or during immunosuppressive therapy should be revaccinated at least 3 months after therapy is discontinued. .
- mechlorethamine
mechlorethamine decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Coadministration with immunosuppressant therapy reduced efficacy of the vaccine may occur. If possible, complete all age-appropriate vaccinations at least 2 weeks prior to initiation of immunosuppressant therapy. Patients vaccinated <14 days before initiation or during immunosuppressive therapy should be revaccinated at least 3 months after therapy is discontinued. .
- melphalan
melphalan decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Coadministration with immunosuppressant therapy reduced efficacy of the vaccine may occur. If possible, complete all age-appropriate vaccinations at least 2 weeks prior to initiation of immunosuppressant therapy. Patients vaccinated <14 days before initiation or during immunosuppressive therapy should be revaccinated at least 3 months after therapy is discontinued. .
- mercaptopurine
mercaptopurine decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- methotrexate
methotrexate decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- methylprednisolone
methylprednisolone decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- muromonab CD3
muromonab CD3 decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- mycophenolate
mycophenolate decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- onasemnogene abeparvovec
onasemnogene abeparvovec decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Adjust vaccinations to accommodate concomitant corticosteroid administration prior to and following onasemnogene abeparvovec infusion. When initiating systemic corticosteriod therapy, wait 2 weeks after an inactivated vaccine.
- oseltamivir
oseltamivir decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- oxaliplatin
oxaliplatin decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Modify Therapy/Monitor Closely. Coadministration with immunosuppressant therapy reduced efficacy of the vaccine may occur. If possible, complete all age-appropriate vaccinations at least 2 weeks prior to initiation of immunosuppressant therapy. Patients vaccinated <14 days before initiation or during immunosuppressive therapy should be revaccinated at least 3 months after therapy is discontinued. .
- ponesimod
ponesimod decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Use Caution/Monitor. If possible, complete all age-appropriate vaccinations at least 4 weeks before initiating ponesimod.
- prednisolone
prednisolone decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- prednisone
prednisone decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- procarbazine
procarbazine decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Coadministration with immunosuppressant therapy reduced efficacy of the vaccine may occur. If possible, complete all age-appropriate vaccinations at least 2 weeks prior to initiation of immunosuppressant therapy. Patients vaccinated <14 days before initiation or during immunosuppressive therapy should be revaccinated at least 3 months after therapy is discontinued. .
- rilonacept
rilonacept decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- satralizumab
satralizumab decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Administer all immunizations according to immunization guidelines. At least 2 weeks before initiating for non-live vaccines. .
- sirolimus
sirolimus decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- tacrolimus
tacrolimus decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- temsirolimus
temsirolimus decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- tocilizumab
tocilizumab decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- tralokinumab
tralokinumab will decrease the level or effect of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Use Caution/Monitor. Limited data are available regarding coadministration with non-live vaccines.
- triamcinolone acetonide injectable suspension
triamcinolone acetonide injectable suspension decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Immune response to vaccine may be decreased in immunocompromised individuals.
- ublituximab
ublituximab decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Administer all immunizations according to immunization guidelines at least 4 weeks before initiating ublituximab for live or live-attenuated vaccines and, whenever possible, at least 2 weeks before initiating for non-live vaccines. Vaccination with live virus vaccines is not recommended during treatment and until B-cell repletion. Do not administer live or live-attenuated vaccines to infants of mothers exposed to ublituximab during pregnancy, before confirming recovery of B-cell counts as measured by CD19+ B cells.
- voclosporin
voclosporin decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Modify Therapy/Monitor Closely. Inactivated vaccines noted to be safe for administration may not be sufficiently immunogenic during treatment.
Minor (2)
- amantadine
amantadine decreases levels of influenza virus vaccine quadrivalent, recombinant by Other (see comment). Minor/Significance Unknown. Comment: Because of its antiviral properties, amantadine may interfere with the efficacy of live attenuated influenza vaccines (LAIV). Coadministration of LAIV and amantadine is not recommended. Inactivated influenza vaccines may be used, as appropriate.
- ozanimod
ozanimod decreases effects of influenza virus vaccine quadrivalent, recombinant by immunosuppressive effects; risk of infection. Minor/Significance Unknown. No clinical data are available on the efficacy and safety of vaccinations in patients taking ozanimod. Vaccinations may be less effective if coadministered with ozanimod.
Adverse Effects
>10%
Injection site tenderness (34-48%)
Injection site pain (19-37%)
Headache (13-20%)
Fatigue (12-17%)
Myalgia (13%)
1-10%
Arthralgia (10%)
Nausea (9%) Chills (7%)
Injection site swelling/bruising (5%)
Injection site redness (4%)
Warnings
Contraindications
Severe hypersensitivity (eg, anaphylaxis) to any component of the vaccine
Cautions
Appropriate medical treatment and supervision must be available to manage possible anaphylactic reactions following administration of the vaccine
Influenza vaccine may not protect all susceptible individuals
If the rare occurrence of Guillain-Barré syndrome (GBS) has occurred within 6 weeks of receipt of a prior influenza vaccine, the decision to give the vaccine should be based on careful consideration of the potential benefits and risks
Expected immune response may not be obtained in immunocompromised individuals, including those receiving immunosuppressive therapy
Pregnancy & Lactation
Pregnancy
Available data on the trivalent or quadrivalent formulations administered to pregnant women are insufficient to inform vaccine-associated risks in pregnant women
Pregnancy outcomes in women who have been exposed to Flublok Quadrivalent during pregnancy are being monitored
Contact: Protein Sciences Corporation 1-888-855-7871
Clinical considerations
- Pregnant women are at increased risk of complications associated with influenza infection compared with nonpregnant women
- Pregnant women with influenza may be at increased risk for adverse pregnancy outcomes, including preterm labor and delivery
Lactation
Unknown if distributed in human breast milk
Consider the developmental and health benefits of breastfeeding along with the mother’s clinical need for the drug, and any potential adverse effects on the breastfed infant from the drug or from the underlying maternal condition
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Contains recombinant hemagglutinin (HA) proteins of the 4 strains of influenza virus specified by health authorities for inclusion in the annual seasonal vaccine
These proteins function as antigens, which induce a humoral immune response, measured by hemagglutination inhibition (HI) antibody
Administration
IM Preparation
Invert the prefilled syringe gently prior to affixing the appropriate size needle for IM administration
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration whenever solution and container permit
If either of these conditions exists, the vaccine should not be administered
Do not mix in the same syringe with any other vaccine
IM Administration
Preferred IM injection site is the deltoid muscle
Storage
Refrigerate between 2-8°C (36-46°F)
Do not freeze; discard if product has been frozen
Protect syringes from light
Do not use after expiration date
Images
Formulary
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