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Flublok

Generic Name: influenza virus vaccine (injection) (in floo ENZ a VYE rus VAK seen)
Brand Names: Flublok, Flublok Quadrivalent

What is Flublok?

Flublok is used to prevent infection caused by influenza virus. Flublok is a new class of influenza virus vaccine made by modern DNA and cell culture technology to produce the right protective ingredients for vaccination. The vaccine is redeveloped each year to protect against specific strains of flu virus.

Influenza (commonly known as "the flu") is a serious disease caused by a virus. Influenza virus can spread from one person to another through small droplets of saliva that are expelled into the air when an infected person coughs or sneezes. The virus can also be passed through contact with objects the infected person has touched, such as a door handle or other surfaces.

Flublok contains recombinant proteins which work as antigens to help your body to develop immunity to the disease. It does not contain egg protein, thiomerosal (mercury derivative), latex, anitbiotics, formaldehyde, gelatin, or live influenza virus.

Flublok will not treat an active infection that has already developed in the body.

Flublok is for use in adults 18 years and older.

Becoming infected with influenza is much more dangerous to your health than receiving Flublok. Influenza causes thousands of deaths each year, and hundreds of thousands of hospitalizations. However, like any medicine, Flublok can cause side effects but the risk of serious side effects is extremely low.

Like any vaccine, Flublok may not provide protection from disease in every person. Flublok will not prevent illness caused by avian flu ("bird flu").

Important information

Becoming infected with influenza is much more dangerous to your health than receiving this vaccine. However, like any medicine, Flublok can cause side effects but the risk of serious side effects is extremely low.

Before receiving this vaccine

You may not be able to receive Flublok if you have:

  • a history of severe allergic reaction to a flu vaccine; or
  • a history of Guillain-Barre syndrome (within 6 weeks after receiving a flu vaccine).

To make sure influenza virus injectable vaccine is safe for you, tell your doctor if you have:

  • a bleeding or blood clotting disorder such as hemophilia or easy bruising;
  • a neurologic disorder or disease affecting the brain (or if this was a reaction to a previous vaccine);
  • a history of seizures;
  • a weak immune system caused by disease, bone marrow transplant, or by using certain medicines or receiving cancer treatments.

You can still receive a vaccine if you have a minor cold. In the case of a more severe illness with a fever or any type of infection, wait until you get better before receiving Flublok.

Vaccines may be harmful to an unborn baby and generally should not be given to a pregnant woman. However, not vaccinating the mother could be more harmful to the baby if the mother becomes infected with a disease that Flublok could prevent. Your doctor will decide whether you should receive this vaccine, especially if you have a high risk of infection with influenza.

It is not known whether influenza virus vaccine passes into breast milk or if it could harm a nursing baby. Do not receive Flublok without telling your doctor if you are breast-feeding a baby.

How is Flublok given?

Flublok is not for use in children. Your child's doctor can recommend the best influenza virus vaccine for your child.

Flublok is given as an injection (shot) into a muscle. You will receive this injection in a doctor's office or other clinic setting.

You should receive a flu vaccine every year. Your immunity will gradually decrease over the 12 months after you receive the influenza virus vaccine.

Flublok vaccine is usually given in October or November. Some people may need to have their vaccines earlier or later. Follow your doctor's instructions.

See also: Dosage Information (in more detail)

What happens if I miss a dose?

Since flu shots are usually given only one time per year, you will most likely not be on a dosing schedule. Call your doctor if you forget to receive your yearly flu shot in October or November.

What happens if I overdose?

An overdose of Flublok is unlikely to occur.

What should I avoid before or after receiving Flublok?

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

Flublok side effects

Flublok will not cause you to become ill with the flu. However, you may have flu-like symptoms at any time during flu season that may be caused by other strains of influenza virus.

You should not receive a booster vaccine if you had a life-threatening allergic reaction after the first shot.

Keep track of any and all side effects you have after receiving Flublok. If you ever need to receive influenza virus vaccine in the future, you will need to tell your doctor if the previous shot caused any side effects.

Get emergency medical help if you have signs of an allergic reaction to Flublok: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • a light-headed feeling, like you might pass out;
  • severe weakness or unusual feeling in your arms and legs (may occur 2 to 4 weeks after you receive the vaccine);
  • high fever;
  • seizure (convulsions); or
  • unusual bleeding.

Common Flublok side effects may include:

  • low fever, chills;
  • redness, bruising, pain, swelling, or a lump where the vaccine was injected;
  • headache, tired feeling; or
  • joint or muscle pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report vaccine side effects to the US Department of Health and Human Services at 1-800-822-7967.

See also: Side effects (in more detail)

What other drugs will affect Flublok?

Before receiving Flublok, tell your doctor if you are using:

  • phenytoin;
  • theophylline; or
  • a blood thinner such as warfarin, Coumadin.

Also tell the doctor if you have recently received drugs or treatments that can weaken the immune system, including:

  • an oral, nasal, inhaled, or injectable steroid medicine;
  • medications to treat psoriasis, rheumatoid arthritis, or other autoimmune disorders--azathioprine, etanercept, leflunomide, and others; or
  • medicines to treat or prevent organ transplant rejection--basiliximab, cyclosporine, muromonab-CD3, mycophenolate mofetil, sirolimus, tacrolimus.

If you are using any of these medications, you may not be able to receive the vaccine, or may need to wait until the other treatments are finished.

This list is not complete. Other drugs may affect influenza virus injectable vaccine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your doctor or pharmacist can provide more information about Flublok. Additional information is available from your local health department or the Centers for Disease Control and Prevention.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Flublok only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2016 Cerner Multum, Inc. Version: 7.09. Revision Date: 2016-10-10, 4:23:27 PM.

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