Skin Prick Allergy Testing is used to find the cause of certain allergies. Allergy testing may be recommended for people with asthma, because allergies can play a significant role in causing asthma symptoms.
An allergy is the way the body's immune system reacts to triggers in the environment such as animal dander and pollen. Allergic symptoms appear when an environmental trigger causes the body to release antibodies, which in turn causes chemicals to be released. These chemicals can cause symptoms of an allergic reaction such as itchy bumps on the skin, wheezing or difficulty breathing.
When testing for these allergies, suspected causes of allergy (such as pollens) are mixed with liquid to make a solution. A drop of each solution is then placed on the skin - usually the forearm. Then, the skin beneath each drop is pricked with a needle. This is usually painless as just the very surface of the skin is pricked. However, this is enough to let a tiny amount of solution into the skin.
The skin is then observed for a reaction. If a reaction occurs, it happens within approximately 20 minutes.
- A positive reaction is when the skin under a drop of solution becomes red and itchy. The bigger the bump, the more sensitive the person is to that specific allergen.
- A negative reaction is when the skin remains normal. This means that you are not allergic to the substance in the solution.