What are the side effects of the influenza vaccine?

Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
Possible side effects of the flu vaccine include soreness and redness or swelling at the injection site. Some people also report low fevers, aches, and some nausea. However, because the vaccine contains a dead version of the influenza-causing virus, you are not at risk of getting the flu from the vaccine itself.

However, if you have had a severe allergic reaction to the vaccine in the past or have an allergy to eggs (the vaccine is an egg product), you may want to reconsider getting the vaccine. Talk with your doctor about which options are right for you.
This content originally appeared on doctoroz.com
Side effects of the influenza vaccine include: muscle aches, low fever, headaches and fatigue. If you receive a flu shot, you also may experience soreness where the virus was injected. It is also possible to have an allergic reaction to an influenza vaccine, although this is rare. If you experience side effects that concern you, discuss them with your doctor.
Different side effects can be associated with the flu shot and nasal spray vaccine.

The flu shot: The viruses in the flu shot are killed (inactivated), so you cannot get the flu from a flu shot. Some minor side effects that could occur are:
  • Soreness, redness, or swelling where the shot was given
  • Fever (low grade)
  • Aches
If these problems occur, they begin soon after the shot and usually last 1 to 2 days. Almost all people who receive influenza vaccine have no serious problems from it. However, on rare occasions, flu vaccination can cause serious problems, such as severe allergic reactions. As of July 1, 2005, people who think that they have been injured by the flu shot can file a claim for compensation from the National Vaccine Injury Compensation Program (VICP).

The viruses in the flu shot are killed (inactivated) or weakened, so you cannot get the flu from the flu shot or nasal spray vaccine. The risk of a flu vaccine causing serious harm or death is extremely small. However, a vaccine, like any medicine, may rarely cause serious problems, such as severe allergic reactions. Almost all people who get influenza vaccine have no serious problems from it.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.