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Flu shot: What are the potential effects?

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The flu shot is a form of protection against influenza. The vaccine is available as a nasal spray or a shot which lowers the chances of acquiring the flu.

The usual side effects after receiving a flu shot are generally mild. Nevertheless, they can be severe in rare instances. Prior to getting a shot, it is best that you are familiar with the possible effects.

Common side effects of the flu shot

The typical side effects of a flu shot are mild and the same among adults, infants and children.

Injection site reactions

The usual side effect of a flu shot is an injection site reaction, usually on the upper arm. Once a shot is given, there is redness, soreness, warmth and even minor swelling in some cases. These effects typically last less than 2 days. The discomfort can be reduced by providing ibuprofen before a shot is administered.

Headache and other bodily aches

When the flu shot is given, it might cause headaches or some form of discomfort in the muscles all over the body.

When the flu shot is given, it might cause headaches or some form of discomfort in the muscles all over the body. This typically arises on the initial day and settles within 2 days. Pain medications such as ibuprofen can help lessen the discomfort.

Fainting or dizziness

Some individuals suffer from fainting or dizziness after receiving the flu shot.

In case the individual tends to become dizzy or dim after a shot, the doctor should be informed before a shot is given. The individual can also sit down for some time after a shot is given and take a snack before or after a shot.


A fever of 101 degrees F or less is a usual effect of the flu shot. A minor fever is generally a minor effect and should settle within 1-2 days. If the fever is bothersome, you can provide acetaminophen or ibuprofen.

Should I get a shot?

A flu shot is usually recommended for everyone, starting 6 months old or older. Remember that anyone at risk for serious complications from the flu must be given a shot such as the elderly over 65 years of age, pregnant women and individuals with chronic ailments.

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