The history of the person's symptoms is important in diagnosing allergies, including whether the symptoms vary according to time of day or the season and possible exposures such as having a pet in the household. Allergy testing is done to see what is cuasing the symptoms (i.e., to identify the specific allergens ): - Skin testing is the most common and useful method. This may include intradermal, scratch, patch, or other tests.
- Less commonly, the suspected allergen is dissolved and dropped onto the lining of the lower eyelid as a means of testing for allergies. (This test should only be done by a physician, never the patient, since it can be harmful if done improperly.)
- In individuals that cannot undergo skin testing (as determined by the doctor), a RAST blood test (to look for IgE antibodies to a specific allergen) may be helpful.
Having allergies may also alter the results of the following tests:
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