What do allergy tests look like

Allergies can manifest themselves in different ways. It is possible to distinguish several types of allergy: skin, inhalation or food allergy. In order to be able to diagnose the right type, it is necessary to perform specialist examinations.
There are three types of tests: blood tests, allergic tests and provocative tests.
Blood tests
Blood tests are performed to detect IgE antibodies that cause allergic reactions in large numbers. IgE is marked in two ways, as total (determines the total amount of antibodies in the body) and specific (targets a specific allergen). However, blood tests are not able to confirm or exclude allergies unequivocally. High levels of IgE can indicate both allergy and kidney, liver and leukemia.
Allergic tests
Skin tests are the most frequently performed allergic tests. Thanks to them, it is possible to precisely identify a given allergen after skin exposure to its effects. These tests may be punctual, intradermal or patch tests.
In the spot tests, drops of solution containing the allergen are placed on the skin and then the skin is pricked. In addition to the solutions, saline and histamine are applied to the skin. The results of the test can be read out after about 20 minutes by measuring the diameter of the bubble.
The intradermal tests are based on the injection of the allergen into the skin. They are performed if the puncture tests are negative and the symptoms still suggest sensitization.
Patch tests are tests that are used to diagnose contact dermatitis. During the test, allergen is soaked in tissue paper rings and placed on the back of the skin. The test result can be read after 48 hours.
Provocative trials
This test consists of delivering a suspicious allergen to the body and observing symptoms. These tests must be carried out under strict medical supervision. In addition, both the allergen and the placebo are given to the patient during this examination (neither the doctor nor the patient should know what was given to make the examination more reliable).
Determining a specific allergen is very difficult, despite the increasing number of tests available.