A skin test is a method of diagnosing allergies. It is also called a scratch test or a puncture test. Skin tests are usually done by an allergist, a doctor who specializes in the diagnosis and treatment of allergies and asthma.
There are two types of skin tests:
1) The prick test, also called the puncture test, is the most common skin test. A small amount of allergen is placed on the skin, and the skin is then pricked with a needle. If you are allergic to the allergen, you will develop a raised, red bump called a wheal.
2) The intradermal test is used less often than the prick test. A small amount of allergen is injected into the skin with a needle. If you are allergic to the allergen, you will develop a raised, red bump.
Skin tests are usually done on the forearm. The allergist will usually test for several allergens at the same time.
The skin test is not painful, but it may cause some itching.
If you are allergic to one of the allergens tested, you will develop a raised, red bump within 15-20 minutes. The bump will go away after 30-60 minutes.
If you do not have a reaction to any of the allergens tested, you are not allergic to them.
Skin tests are the most common way to diagnose allergies. They are quick, easy, and relatively painless.