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Influenza Vaccine


The influenza vaccine

is an injection given to help prevent influenza (flu). The flu is caused by a virus. The virus spreads from person to person through coughing and sneezing. Several types of viruses cause the flu. The viruses change over time, so new vaccines are made each year. The vaccine begins to protect you about 2 weeks after you get it. The flu vaccine is usually injected into the upper arm. It may be given in your thigh.

Call your local emergency number (911 in the US) if:

  • Your mouth and throat are swollen.
  • You are wheezing or have trouble breathing.
  • You have chest pain or your heart is beating faster than normal for you.
  • You feel like you are going to faint.

Call your doctor if:

  • Your face is red or swollen.
  • You have hives that spread over your body.
  • You feel weak or dizzy.
  • You have increased pain, redness, or swelling around the area where the shot was given.
  • You have questions or concerns about the influenza vaccine.

When to get the flu vaccine:

The vaccine is offered every year starting in early fall. Get the vaccine as soon as it is available. Children 6 months through 8 years old need 2 doses during the first year they get the vaccine. The 2 doses should be given at least 4 weeks apart. It is best if the same type of vaccine is given both times. The child can then receive 1 dose each year. Children 9 years or older should get 1 dose each year.

Immunization Schedule 2018

Who should get the flu vaccine:

Talk to your healthcare provider if you have concerns about the flu vaccine. In general, the following groups should get the vaccine:

  • Infants 6 months or older
  • Any healthy adult who would like to decrease the risk for the flu
  • Anyone living with or caring for children younger than 5 years
  • Healthcare workers
  • Anyone who lives in a long-term care facility
  • Anyone who has chronic health problems, such as asthma, diabetes, or blood disorders
  • Anyone who has a weak immune system
  • Women who are or will be pregnant during the flu season

Who should not get the flu vaccine or should wait to get it:

Anyone who is sick or has a fever should wait until he or she is well before getting the vaccine. The following should not get the vaccine:

  • Infants younger than 6 months
  • Anyone who has had an allergic reaction to the flu vaccine
  • Anyone who received a diagnosis of Guillain-Barré syndrome within 6 weeks of getting a flu vaccine
  • Anyone who is allergic to thimerosal (mercury)

Flu vaccine and egg allergies:

The flu vaccine may contain a small amount of egg protein. The amount is so low that it is not likely to cause an allergic reaction. Tell your healthcare provider if you have an egg allergy before you get the flu vaccine. Describe all the signs and symptoms of allergic reaction you have had to eggs. Examples include hives, swelling, and trouble breathing. Based on your reaction to eggs, you may need to go to a hospital, clinic, or other facility to get the flu vaccine. Providers need to be able to respond to the rare risk that you have a severe allergic reaction. Egg-free vaccines may be available, but do not delay getting a flu vaccine to wait for it.

Risks of the flu vaccine:

The flu vaccine may cause mild symptoms, such as a fever, headache, and muscle aches. It may also cause mild to moderate soreness or redness at the area where you were given the injection. You may still get the flu after you receive the vaccine. You may have an allergic reaction to the vaccine. This can be life-threatening.

Apply a warm compress

to the injection area to decrease pain and swelling.

Follow up with your healthcare provider as directed:

Write down your questions so you remember to ask them during your visits.

© Copyright IBM Corporation 2018 Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes. All illustrations and images included in CareNotes® are the copyrighted property of A.D.A.M., Inc. or IBM Watson Health

The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Learn more about Influenza Vaccine (Ambulatory Care)

Associated drugs

IBM Watson Micromedex