Allergy Skin Test: MedlinePlus Medical Test
What is an allergy skin test?
An allergy is an overreaction, also known as a hypersensitivity, of the body’s immune system. Normally, your immune system works to fight off foreign substances like viruses and bacteria. When you have an allergy, your immune system treats a harmless substance, like dust or pollen, as a threat. To fight this perceived threat, your immune system reacts and causes an allergic reaction. Symptoms of an allergic reaction can range from sneezing and a stuffy nose to a life-threatening condition known as anaphylactic shock.
There are four main types of overreactions, known as Type 1 through Type IV hypersensitivities. Type 1 hypersensitivity causes some of the most common allergies. These include dust mites, pollens, foods, and animal dander. Other types of hypersensitivities cause different immune system overreactions. These range from mild skin rashes to serious autoimmune disorders.
An allergy skin test usually checks for allergies caused by Type 1 hypersensitivity. The test looks for reactions to specific allergens that are placed on the skin.
Other names: type 1 hypersensitivity skin test, hypersensitivity test allergy scratch test, allergy patch test, intradermal test