Influenza virus vaccine (injection)

Influenza virus ("the flu") is a contagious illness caused by a virus that can spread from person to person through the air or by touching surfaces. Symptoms of the flu include fever, chills, tiredness, body aches, sore throat, cough, vomiting, and diarrhea. The flu can also lead to sinus infections, ear infections, bronchitis, or serious problems like pneumonia.

Influenza virus vaccine is for adults and children to help prevent infection caused by the influenza virus. This vaccine helps your body build immunity to the disease but will not treat an infection that you already have.

This medication guide focuses only on the injectable form of this vaccine.

Like any vaccine, the influenza virus vaccine may not protect every person from the disease.

Influenza virus vaccine will not make you sick with the flu virus.

Getting infected with the influenza virus may be more harmful to your health than getting this vaccine.

You may not be able to receive this vaccine if you have ever had a severe allergic reaction to a flu vaccine or any of its ingredients.

Tell your vaccination provider if you are allergic to eggs. Some flu vaccines contain egg protein.

Tell your vaccination provider if you have:

• fever;
• fainted after receiving an injection;
• a weak immune system (caused by disease or by using certain medicine); or
• a history of Guillain-Barre syndrome (within 6 weeks after receiving a flu vaccine).

Tell your vaccination provider if you are pregnant, plan to become pregnant, or are breastfeeding.

Get emergency medical help if you notice signs of an allergic reaction: hives, trouble breathing, swelling of your face, lips, tongue, or throat.

Some children aged 6 months to 4 years may have a higher risk of having a seizure caused by fever during the first day after vaccination. Inform your vaccination provider if your child has ever had a seizure. Contact your doctor immediately if your child has a seizure.

Keep a record of any side effects you experience. If you get this vaccine again in the future, you may need to inform the vaccination provider if the previous shot caused any side effects.

Influenza virus vaccine will not make you sick with the flu virus. You may experience flu-like symptoms at any point during flu season that might be due to other strains of the influenza virus.

Getting infected with the influenza virus may pose a greater health risk than receiving this vaccine. However, like any medication, this vaccine can cause side effects, but the chance of serious side effects is very low.

Influenza virus vaccine may lead to serious side effects. Contact your doctor immediately if you have:

• a light-headed feeling, as if you might faint; or
• nervous system issues—numbness, pain, tingling, weakness, burning or prickly sensations, vision or hearing problems, difficulty breathing.

Common side effects of the influenza virus vaccine may include:

• pain, redness, tenderness, swelling, bruising, itching, or a hard lump at the injection site;
• diarrhea, loss of appetite;
• muscle or joint pain;
• fever;
• headache, tiredness, general feeling of being unwell; or
• fussiness, crying, or drowsiness in a child.

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

Read all vaccine information sheets provided to you.

Follow your doctor's instructions or the schedule recommended by your local health department.

Your vaccination provider, pharmacist, or doctor can recommend the best influenza virus vaccine for your age.

This vaccine is given as an injection (shot) into a muscle.

Children 6 months through 8 years of age may need 2 doses during the same flu season, given at least 4 weeks apart.

Since the influenza virus vaccine is redeveloped each year for specific strains of influenza, you should receive a flu vaccine every year.

Be sure to get all recommended doses of this vaccine or you may not be fully protected against disease.

An overdose of this vaccine is unlikely to happen.

Follow your vaccination provider's instructions regarding any limits on food, drinks, or activities.

Before getting this vaccine, inform your vaccination provider about all other vaccines you have received.

Other medications may impact the influenza virus vaccine, including prescription and over-the-counter medicines, vitamins, and herbal products. Inform your doctor about all other medicines you are taking.