ALLERGY TESTING IN THE PHOENIX VALLEY

Allergy Skin Testing

Prick skin allergy testing, also known as scratch testing, is one type of allergy testing. A small disposable prick device applies the allergy extract to the skin and then scratches or pricks the skin. Common allergy testing extracts are grasses, weeds, trees, house dust, animals, and molds. A hive or raised bump will occur at the site of the prick. Each test site will be measured and specific allergies of the patient identified. Prick testing may be applied to the forearms or the back depending upon the age of the patient, the number of tests ordered, and the condition of the skin.

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Food Testing

Food allergy testing may be initially performed by scratch skin testing.  If indicated, a graduated oral food challenge over few hours can be performed in the medically safe environment of the office. Another type of food testing known as a RAST or Immunocap testing involves examining specific IgE in the blood.

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Patch Testing

Patch testing to specific chemicals, metals and other substances determines if the patient has a delayed hypersensitivity reaction. A strip of substances or customized patches are applied to the skin of the back. Potential reactions are evaluated in the office at 48 hours and 72 hours after application of the test substance.

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Venom Testing

Venom testing checks for allergy to a group of insects known as hymenoptera. Allergy testing for honey bee, wasp, yellow jacket, yellow hornet, and white hornet is available. Testing involves both scratch testing and intradermal testing. Venom immunotherapy is available to patients with positive test results who have a history of potential life threatening reactions to bee stings.

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Antibiotic Testing

Testing for drug allergies, such as antibiotics, is available. Commonly tested antibiotics are penicillin and the cephalosporins. Allergy testing begins with a scratch test of a weakened dilution of the drug. Intradermals are the next level of testing.  If skin testing is negative a final part of the testing in the office is a graduated oral challenge to the medication. Patients with negative results to the test drug will then be instructed on how to complete the rest of the challenge.