About Allergy Testing in Children

Twenty percent of Americans suffer from allergies, including allergic asthma. That is one in every five adults and children. Eight percent of children younger than 6 will have a food allergy. There are different types of allergies, so singling out the cause in children will often require testing for specific allergens. There are a few effective and accurate tests that can be performed, depending on what is best for the child.

General Evaluations

• Before a child is tested for allergens, individual and family histories with allergies and asthma will be taken into consideration. An evaluation of the child and family's history will single out possible allergens to be tested. Certain general tests will then be taken to determine if the child is experiencing reactions to allergens. These tests include a physical examination to identify signs of an allergy and tests to determine sensitivity to certain allergens.

Skin Test

• One of the more common tests for allergens in children is the skin test. The skin test is 90 percent accurate and is also the least expensive and time consuming. The skin test is performed with a simple prick of a needle on a child's arm or back. An allergen is inserted into the skin to determine whether the child is sensitive. If the child is allergic, a red, itchy bump should appear within 15 minutes. The size of the bump determines the level of sensitivity. If the bump is large, then the child is more sensitive to the allergen. Prior to taking this test, children should avoid any medications, such as antihistamines.

Blood Test

• Like the skin test, the blood test is highly accurate and is also an alternative to children who might be uneasy about taking the skin test. The blood test, or RAST (radioallergosorbent test), is done through the use of radioactive or enzyme markers that will identify signs of IgE antibodies or allergens in the child.

Elimination Diet

• If a child has a possible food allergy, then certain foods, such as milk, wheat or peanuts, are eliminated in the child's diet to single out a specific cause. The child is monitored for four to seven days to determine if there is a decrease in her allergic reactions. If there are no signs of change, then additional foods are eliminated until there is a positive reaction in the child's health. This type of test is always difficult to perform because of the child's dietary habits and tastes, and also because of the difficulty of singling out allergens found in packaged or processed foods. Many of these allergens are often found in hidden ingredients, therefore making it difficult to determine what is the exact cause for the allergic reactions.

Other Tests

• There are other tests that can be performed on children, but they are considered unproven and ineffective. If a physician suggests any of these tests, then it's always best to seek out a second opinion. These tests include: cytotoxicity blood test; electroacupuncture biofeedback; urine autoinjection; skin titration; sublingual provocative testing; candidiasis allergy theory; and basophil histamine release.