According to the Asthma & Allergy Foundation of America's California chapter, an allergy occurs when a person has a reaction to a substance that's usually harmless. Food, drug and environmental allergens exist, and it's important that the source of an allergy be identified so a person can avoid it. Allergies can be dangerous and deadly; however, they are common. See your doctor to help identify the trigger for your allergy symptoms and help you come up with an appropriate response plan for your symptoms.
Recording Symptom History
When a person has allergy symptoms such as sneezing, itching, or rashes, he should write down what happened the day before the symptoms appeared. This includes activities, locations visited, medications taken, food intake and anything he may have been in contact with. This is especially helpful when symptoms recur.
Physical Exam
According to the Asthma and Allergy Foundation, a doctor can examine the sinuses, eyes, ear, nose and throat during an exam. A pulmonary function test and chest X-ray may be done. In addition, any rashes or skin reactions are observed. This exam can help confirm an allergic reaction and rule out other issues.
Skin Tests
Skin tests include a scratch test or an intradermal needle injection into the first layer of skin. The purpose is to expose the patient to the allergen or different allergens to identify whether a reaction occurs. The size of the hive or "wheal" that develops identifies the amount of sensitivity that a person has to the allergen. According to the Asthma and Allergy Foundation, the patch test determines whether a person has contact dermatitis to a particular allergen. The allergen is placed on the skin and covered with a bandage.
Blood Tests
The Asthma and Allergy Foundation reports that the different blood tests available include allergen blood tests (RAST), enzyme-linked immunosorbent assays (ELISA), fluorescent allergosorbent tests (FAST), multiple radioallergosorbent tests (MAST), or radioimmunosorbent tests (RIST). These tests identify whether the blood has antibodies to a particular allergen. These tests can help if the person has a skin problem that might prevent her from taking a skin test or is taking medications that interfere with the skin testing results.
