After the reaction begins, the area will probably itch or burn. People with dermatitis or other skin irritations may have the test performed at different locations on the body. The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experience, and level of trust. The injection site will show a greater than 5 mm inflammation zone at the test site of the test antigen . There should be less than a 5 mm inflammation zone of the disease antigen.
Some skin tests are less accurate than others.
Tests for food allergies may be less accurate than disease antigen testing. What Abnormal Results Mean An inflammation zone of less than 5 mm indicates the immune system may be unable to react to any antigen . Other tests may be performed to determine if the person has been exposed to an antigen. What The Risks Are A very small amount of the antigen is injected, so the risks are minimal. Typical reactions include itching and hives .