• Identifying the specific allergens is an important part of allergy management.
• Allergy Tests help to identify these through skin prick or RAST to measure the amount of IgE.

• Children or adults who have persistent or difficult to control allergic conditions should be tested.
• These conditions include moderate to severe asthma , asthmatics on high dose steroids , eczema, rhinitis and conjunctivitis.
• Children or adults who have several food restrictions without confirmation of a food allergy should be evaluated.

• Prior to the Tests
• Stop medications with antihistamine like effects ( these include antihistamines, cough and cold syrups and tricyclic antidepressants in adults)
• These medications need to be stopped for a period of at least 3-5 days
• You will also need to avoid moisturizers and creams for a similar period of time to prevent the allergen from running off the skins surface. The test should be performed on normal skin which is free of any rashes.
• Please do not stop your rhinitis/ asthma medications ( inhaled nasal steroids/ventolin , preventer inhalers or singulair).
• How are the allergy tests done ?
• Usually the forearm is the preferred site , however in young children the back may be used
• The Skin prick tests involve putting a small amount of the suspected allergen which is commercially prepared on the marked area of the skin.
• The allergen is then pricked through with a fine needle. The test is safe and painless and can be done on babies.

• This test involves obtaining a small sample of blood to see if the individual is allergic to the common allergens.
• This test is not as sensitive as the skin test, is more painful.
• This test is suitable for those who cannot be taken off antihistamines / for those who have severe eczema.

Each test has its advantages. The skin test is a good initial screening test that is quick, safe and inexpensive.

These tests have an excellent negative predictive value (meaning that a negative test indicates that substance is NOT cause of the allergy). However the positive predictive value is so-so (meaning that a positive test is not always accurate). Your doctor is the best person to interpret the results.

In Addition the range of allergens used and the the technique is very important. If done incorrectly false negative and false positive may arise. Therefore it should ONLY be done by a Specialist with Allergy Training.