Allergies: To Test or Not to Test

Allergy testing not necessarily needed

(RxWiki News) So you think you're allergic to something you inhaled, touched or ate. But without any obvious symptoms, it's hard to tell exactly what you're allergic to. And experts say allergy testing may not always be useful.

The American Board of Internal Medicine (ABIM) has partnered with a number of specialty societies in a campaign called Choosing Wisely. For this campaign, experts have developed lists of tests and procedures that patients should discuss with their doctors.

One of these lists was written with the help of the American Academy of Allergy, Asthma and Immunology (AAAAI).

According to the AAAAI and Choosing Wisely, patients should think twice about allergy testing.

But why?

Evidence shows that random allergy testing usually doesn't help identify allergies. In addition, unnecessary tests may lead to unnecessary lifestyle changes or may be just a waste of money.

"Try to manage allergies on your own before requesting tests."

Skin and blood tests can help doctors find out if you are actually allergic to something. However, such testing may not be the best first step in your battle against allergies.

According to a Choosing Wisely report, "Random allergy testing doesn't usually help."

Allergy tests are now available in places beyond the doctor's office. Patients can get screened at drugstores or supermarkets. They can even buy home testing kits. However, random allergy testing may show allergic reactions that people don't experience in day-to-day life.

Furthermore, screening for food allergies may be focused on the wrong signs. Food allergy screening can involve tests for a protein called immunoglobulin G (IgG). But researchers have yet to prove the usefulness of the IgG test. In fact, food allergies are related to a different protein - called IgE.

The report warns that unnecessary tests may lead you to unnecessarily change your lifestyle. Some tests may show you are allergic to something you are not. 

For example, you may have to give up foods like wheat, soy, eggs or milk. Cutting out certain foods from your diet could lead to nutritional problems or make you feel "unnecessarily worried when dining out or buying groceries." A false alert about pet dander allergies might make you give up a beloved pet when you don't need to. 

The report also explains that getting the wrong test could be a waste of money. "Inappropriate tests won't help diagnose your problem or improve your treatment, and can be expensive," the report reads. 

Depending on how many allergies you're being screened for, a skin allergy tests can cost from $60 to $100. A blood test may cost anywhere from $200 to $1,000.

According to the report, "An IgG blood test can cost hundreds of dollars, and might not be covered by your plan. An extensive evaluation of chronic hives can cost thousands."

The report takes time to note that allergy testing isn't always uncalled for. If you can't control your allergies with self-help or over-the-counter drugs, it is probably time to see a doctor. Your doctor may run tests or refer you to an allergy expert for further testing.

For a skin test, your doctor will prick your skin with a tiny amount of a possible allergen. If you have a rash or take medications that affect skin testing, you may receive an IgE blood test. 

If you have chronic hives (red and sometimes itchy bumps on the skin), you may not need tests at all. However, your doctor may use tests to eliminate non-allergic causes like thyroid disease, lymphoma or lupus.

Before requesting testing, try to manage allergies on your own:

  • If you think you're allergic to a food, the only treatment is to avoid that food. Read food package labels and ask about ingredients when eating at restaurants.
  • If you have outdoor allergies like hay fever, keep track of pollen counts with the National Allergy Bureau.
  • If you have indoor allergies, using air conditioning or a dehumidifier, and keep your house clean.
  • Over-the-counter medications may also help control both indoor and outdoor allergies.

This report and other things patients and doctors should question can be found at the Choosing Wisely website.

Reviewed by: 
Review Date: 
February 28, 2013