Allergies are overreactions of the body's immune system to specific substances that it misidentifies as harmful. Some people have allergic reactions to several things; for example: flowers or animals. The reaction is commonly caused by contacting or eating the specific thing. The symptoms of allergies are different: it can be flushing of the skin, problems with breathing, sneezing, itchy eyes, etc. Every allergy has its own, unique symptoms. Some allergies are really dangerous and can even cause death.