When Is Allergy Testing Necessary?


So, what's your primary allergy trigger? Pollen, mold or maybe your pets?

If you do not know what causes your allergies or asthma to flare, how can you avoid further contact with your particular irritant?

If you have suffered from allergies for a number of years, or have the added concern of allergy-triggered asthma attacks, it may be time to get tested. Allergy testing is the most efficient way to determine what exact element in your environment is causing your body to react. Rather than avoid all of the possible allergens both indoors and outside, once you know your allergy type, you can stop stressing and target the cause alone.

So, why lock yourself indoors to avoid pollen if you're really allergic to mold (that will grow in your home anyway?) Or why rip up your carpets and ditch your curtains to keep away dust mites when bathing your pets in anti-allergy shampoos would offer you more relief?

Here are a few common tests to determine the cause of your allergies:

RAST Allergy Test

For this test, a small amount of blood is drawn and tested. Later, a lab technician will add trace amount of allergens with some of the patient's drawn blood. Under a microscope, the amount of allergy antibody or IgE is produced by the blood is measured and used to determine how allergic you are to the allergen. Usually this method is better in cases of severe reactions, because only a small sample of blood is reacting to the allergens instead of your whole body.

Skin Prick or Scratch Test Allergy Test

This is the most common type of allergy testing- it is very effective and inexpensive. This test involves placing a small amount of allergen on the skin of the forearm, upper arm or back and then scratching or pricking the skin so that the allergen penetrates the skin's surface. Any allergen that produces a reaction will cause the skin to turn a bit red and swell slightly, so that it looks a bit like a mosquito bite. Several allergens can be tested at the same time and it only takes 20 minutes to get the results.

Intradermal Allergy Test

This second method of skin testing is more sensitive and yields very consistent results. For this test, a small amount of allergen to be injected just under the skin's surface. Several allergens can be tested at once and after about 20 minutes, a small hive or red, swollen area with appear on the skin.

How to Prepare for Testing:

  • Before being tested, stop taking all antihistamines or else the results of the test may not be accurate. Typically your doctor will tell you what medicines to avoid taking before the test.
  • The allergist or healthcare provider performing the test will ask for a detailed medical history as well as questions about past illnesses, eating habits, lifestyle, work environment, emotional and social conditions, etc. All of this information helps them in determining the cause and prescribed treatment of you allergies.

What You Can Expect After an Allergy Test:

  • In cases where your skin is pricked or scratched, you may feel mild discomfort. If you have a "positive reaction" (allergic reaction) to one of the sample allergens used in the test, the area may be itchy for a little while.
  • If you are worried about having a severe reaction, bring along some benryryl or other antihistamine to take after the test is completed.
  • After it is determined what allergens you are most sensitive to, you will be better able to avoid exposure, which in turn will reduce your dependence on medicines to control symptoms.