You do not need to prepare for allergy tests, but in order for the tests to be reliable, you should remember about a few important things.Allergy tests are performed in case of suspicion allergies. They make it possible to determine to which allergen the patient is allergic and how severe the allergy is. Thanks to the tests, the doctor can choose the drugs in an appropriate way, and the allergy sufferer learns from which substances he should stay as far away as possible. There are so many sensitizing substances that it is impossible to test them all in one test (conduct several tests at the same time). Based on the medical history, the allergist decides which allergens should be included in a specific test and what type of test it should be.
Skin tests – standard examinationThis is the basic method that determines what the patient is allergic to. This applies to both suspected inhalation and food allergies. Most commonly used spot tests. Before the test, remember to stop taking desensitizing drugs for at least a week, which may interfere with its results. Do not use any ointments or gels on the area of the skin where the tests will be performed. The tests consist in applying drops of solutions containing various allergens to the inside of the forearm (each drop is one allergen). After introducing allergens with a special «lancet» or a thin needle under the epidermis, the patient waits for about half an hour. Next, the doctor assesses the resulting blisters on the skin in terms of size and degree of redness, which ultimately gives certainty what factor causes the allergy and how strong it is. The patient finds out about the results on the spot and the doctor can start treatment right away.
Depending on the patient, other types of skin tests are also practiced, such as sticking on the back patches impregnated with allergens (the point method is also used on the back, when there are more than a dozen allergens to be tested). Most often, patches are used in small children or older children who are terrified of punctures and needles. The patches are not invasive in any way, but their downside is wearing them for 24 hours. Only after this time has elapsed, the doctor can evaluate the results. Testing is also possible intradermal method – the patient is injected with small doses of allergens directly into the skin. The doctor then assesses their immediate or delayed response (after 24, 48 and 96 hours). This method is therefore much more time and labor intensive, but more accurate.
Blood tests
However, it is not always possible to perform skin tests. In the case of children under three years of age, people with skin diseases, and patients who, due to a very strong allergy, must constantly take antihistamines, specialist blood tests are performed. They consist in the determination of IgE antibodies to the main pollen, mite, mold and animal allergens.