A post-injection inflammatory reaction is swelling, irritation, and other problems that develop after a person gets an injection. The reaction can develop at and around the injection site or far away from the injection site. It can develop right away and last for a short period of time. Or it can develop weeks after the injection and last for several hours or days.
CAUSES
This condition may be caused by:
An allergy.
A response by your body's immune system (immune response).
Damage to the surrounding tissue from the injection.
Germs that enter the body through the injection site.
SYMPTOMS
Symptoms of this condition include:
Itching.
Redness.
A rash.
Warmth.