Allergy Testing

Allergy testing, also known as skin, prick or blood testing, is a method for determining to what substances a person is allergic.

Skin allergy testing is the most common, reliable and relatively painless form of allergy testing. A very small amount of certain allergens is put into your skin by making a small indentation or “prick” on the surface of your skin. A skin allergy test determines specific allergens based on skin reactions. You don’t have to wait long to find out what is triggering your allergies. Reactions occur within about 15 minutes.

If you have allergies, just a little swelling will occur where the allergen(s) which you are allergic to was introduced. For instance, if you are allergic to ragweed pollen but not to cats, only the ragweed allergen will cause a little swelling or itching. The spot where the cat allergen was applied will remain normal. 

Blood tests are generally used when skin tests might be unsafe or won’t work, such as if you are taking certain medications or have a skin condition that may interfere with skin testing.

There are methods of allergy testing that the American Academy of Allergy, Asthma & Immunology (AAAAI) believes are not useful or effective. These tests are performed by non-allergy practitioners or people who call themselves healthcare professionals but lack formal training and national board-certification in the field of allergy and immunology. .

Spirometry

Spirometry measures how much air you can inhale as well as how much and how fast you can exhale air. It is an important tool to diagnose and understand asthma severity and control.

Spirometry for asthma is used:
• During your first visit with an allergist / immunologist
• After treatment has started and your symptoms and peak expiratory flow have stabilized
• To document your best airway function
• At least once yearly to assess maintenance of airway function, regardless of medication (changes)
• To evaluate the response to a change in therapy

Fractional Excretion of Nitric Oxide

A FeNO test or exhaled nitric oxide test, in patients with allergic or eosinophilic asthma, is a way to determine how much lung inflammation is present and how well inhaled steroids are suppressing this inflammation. With allergic or eosinophilic asthma, sometimes you may feel your breathing is fine, but when you measure your exhaled nitric oxide, it may still be significantly elevated, and you might do better in the long-term using slightly more of your inhaled steroid to suppress this inflammation.