In order to best manage your allergy symptoms, it is necessary to determine what is causing them. Allergy testing is able to provide specific information about your allergic triggers. Once this has been determined, your allergist can develop a treatment plan specific to your triggers, symptoms and lifestyle.
Skin prick testing involves placing an allergen on the skin and pricking the skin through this extract. If you are allergic to the substance, a localized small, itchy bump (resembling a mosquito bite) develops within twenty minutes. This reaction is transient.
Most commonly, allergists opt to perform skin testing, as it is safe, reliable and leads to a prompt, tailored management plan.
Blood testing can also be used for diagnosis of allergies, although skin testing is usually the preferred method. Blood testing can be useful when skin tests cannot be performed, such as in those with skin conditions that interfere with placement and interpretation of a skin test, or in those patients taking medications that interfere with the skin test reaction. It is often used in conjunction with skin testing to follow changes over time in those with food allergy.
There are other types of blood tests available, such as measurement of IgG antibodies, but it is important to note that specific IgG antibodies have no known clinical value in assessing allergies and, in general, this type of testing is discouraged.