What are Common Flu Shot Side Effects?

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Injected Flu Vaccine

Most people experience few or no side effects when they get a flu shot, but some do have certain reactions. The reaction you have will depend somewhat on the type of flu vaccine you get. There are several different types of injected flu shot, which typically cause the same types of side effects.

The most common flu shot side effects include:

  • Pain or soreness at the injection site
  • Low grade fever
  • Feeling tired
  • Headache
  • Sore or achy muscles
  • Itching at the injection site
  • Redness or toughness at the injection site

FluMist Nasal Spray Flu Vaccine

If you get the nasal spray flu vaccine (FluMist), you obviously won't have any injection site problems since it is not a shot. However, the nasal spray vaccine can cause a few different side effects.

These may include:

  • Feeling tired
  • Low grade fever
  • Slightly sore or achy muscles
  • Minor upper respiratory symptoms (such as runny or stuffy nose or mild cough)
  • Sore throat
  • Wheezing (in children)
  • Vomiting (in children)

More serious side effects of the flu shot are very rare. If you think you might be experiencing a serious reaction to the flu vaccine, contact your health care provider or seek medical attention right away.

Allergic Reactions

If you experience symptoms of an allergic reaction such as difficulty breathing, swelling of the throat, mouth, tongue or face or widespread uncontrollable itching, seek medical attention immediately.

Guillain Barre Syndrome

Although it has not been irrefutably linked to the flu vaccine, people with a history of developing Guillain-Barre syndrome within 6 weeks of a previous flu vaccine should not get another one. Characterized by numbing and paralysis of the extremities which gradually moves inward, Guillain-Barre can be life threatening.

If you notice symptoms of this syndrome, contact your health care provider.

If you believe you have suffered a serious side effect from a flu vaccine (or any other vaccine), you can file a claim with the National Vaccine Injury Compensation Program.


"Intradermal Influenza (Flu) Vaccination." Seasonal Influenza (Flu). 16 Jul 12. US Centers for Disease Control and Prevention. 25 Aug 12.

"National Vaccine Injury Compensation Program." Health Resources and Services Administration. US Department of Health and Human Services. 27 Aug 12.

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