What are the risks of the flu shot?
It may cause mild problems, such as soreness, redness, and swelling on the arm where you got the shot. You might also have a fever and muscle aches for a day or two after you get the shot. The risk of a serious problem from the flu shot (such as a severe allergic reaction) is very small. The viruses in a flu shot are killed, so you cannot get the flu from a flu shot. If you need more information, see the topic Influenza.
