If you think you have had an allergic reaction it is important to see a doctor. Your doctor can then refer you to an allergist who can confirm if you are allergic. Here are some of the ways a diagnosis is made:

Patient History

Your doctor may ask you these questions to get a better understanding: 

• What happened when the reaction occurred (e.g., symptoms)?
• Where did it happen?
• When did the reaction first start?
• How long did it last?
• What treatments were used?
• Do any other family members have allergies?

Skin Prick Test

This is the most common test used by allergists. Typically, a small drop of the allergen is placed on a person's arm. The skin is then pricked with a special needle so the body can absorb the allergen. After about 15-20 minutes the skin is examined to see if there is any redness or swelling (a wheal). The result will be measured and recorded and then the allergist will determine if it is a positive reaction.

Blood Tests for Allergies

When a person is allergic to something, their immune system reacts by making antibodies called IgE (immunoglobulin E) specific to the allergen (supposedly to protect the person against the allergen). Blood tests measure the level of IgE in the body. A blood sample is taken and then mixed with the allergen to see if there is a reaction.

Food Challenge Test

This test should only be done in a medical facility under the supervision of an allergist. If a person seems to have outgrown their allergy then this test may be used. An allergist feeds the patient increasing amounts of the food being tested. If the food being challenged is tolerated well without any reaction occuring, then the patient is no longer considered allergic to it.

Once an allergy has been confirmed it is important to remember to:

• Avoid your allergen and prevent future reactions.
• Carry an epinephrine auto-injector (e.g., EpiPen® or Twinject®) at all times.
• Wear medical identification such as a MedicAlert® bracelet (or necklace, when age appropriate).
• Have a written Anaphylaxis Emergency Plan that describes the signs and symptoms of anaphylaxis and instructions on when and how to use epinephrine.