The measurement of Total IgE will indicate if a patient is allergic or not. If it is unclear if you are allergic or not to inhaled substances, your doctor can order a simple screening test for inhalant allergy, called the Phadiatop test, which can be done by your laboratory. If the Phadiatop test result is positive, you are definitely allergic and further RAST tests should then be done to identify the cause of your symptoms, since these are due to inhaled allergens. Return to Top A pathologist can also identify the cause of an allergy in the laboratory by studying a small sample of the patient's blood. If he finds high levels of the IgE antibody to a particular substance, using the RAST test, or CAP RAST, it will confirm that you are allergic to that substance.
Laboratory tests are accurate, convenient and have a broader range of allergens than the skin tests.
It is possible to test for allergy to over 300 environmental substances in the laboratory. Laboratory test are also more suitable for small babies and patients with eczema in whom skin tests are difficult to perform. The costs of laboratory tests can be greatly reduced by using screening panels of appropriate individual RAST tests. Skin Tests Return to Top Skin tests can be performed by your doctor in his rooms or at an allergy clinic of a hospital. Skin tests are painless and give a quick result.