I received a flu shot yesterday. Why does my arm hurt so bad?

Flu shots are painful because someone is jabbing a pointed bit of metal into your arm and forcing fluid into your body. But why does it sometimes hurt more the next day? And while we're at it, why does the shot even go in the arm? read more

Generally, the flu shot is placed in your deltoid muscle. They must stick a needle through your muscle tissue, and occasionally you can hit a nerve. The muscle tissue they went through will generally feel bruised. read more

Muscle inflammation. Flu vaccines are generally injected into the deltoid, the muscular part of the arm. It causes inflammation of the area and followed by a slight immune reaction (desired effect). read more

If you receive your flu shot as an intramuscular injection, you have a 10 to 64 percent chance of experiencing some soreness, reports the Centers for Disease Control and Prevention. This temporary, mild arm soreness is substantially less bothersome than the whole-body achiness you’d experience if you had skipped the shot and ultimately caught the flu. read more

I received the flu shot last October, 2017, because it is mandatory in my nursing college. The shot was given in my left deltoid. Since that time I experienced extreme pain in my left arm, and the pain radiated up into my neck,making it hard to sleep for about 2 weeks. read more