What is allergy testing?
Allergy testing shows which allergens in the environment trigger your allergies, so you can avoid those allergens and further treatment can be planned.
How is allergy testing conducted?
1. Skin Test = Skin prick test
The test involves placing a small amount of the suspected allergy-causing substance (allergen) on the skin and then scratching or pricking the skin so that the allergen is introduced under the skin surface. The pricking does not cause any wound. After 15 minutes, if you are allergic to any allergens, signs of a reaction, which usually include swelling and redness of the site similar to a mosquito bite, will occur.
2. Rast Test = A blood test to find the antibody that causes allergy
The test involves collecting a blood sample and costs more and takes longer time than the skin test. The procedure is performed when the patient cannot take the skin test.
Preparation before undergoing a skin test:
- Stop all allergy medications antihistamine, cough medicine, cold medicine, and antipruritic for 3-7 days before taking the test, depending on the types of medicine.
- If you are using an inhaler or a nasal spray, you can continue using it until your appointment.
- You can still eat and drink prior to the test.