Allergy diagnosis frequently includes skin testing. Skin testing can include prick or puncture testing and intradermal testing.
The prick test involves a very superficial puncture of the surface of the skin with various allergen containing extracts. An allergen is a substance made from sources that cause allergies such as pollen, animal dander and insect venoms.
If you are allergic, you will develop a small itchy red bump at the site of the puncture. This usually takes about 15 minutes to develop. If we are testing for common airborne allergens then a total of about 30 little punctures are made usually on the arm. The reaction to the skin test is measured in 15 to 20 minutes.
If the prick test is negative then we may decide to do slightly stronger tests by injecting tiny amounts of allergen into the superficial layers of the skin to detect milder allergies.
If your arm is very itchy after the skin testing we can treat with a topical antihistamine or an antihistamine pill but this is usually not necessary. More severe reactions to skin testing rarely occur.