Advantages of RAST Test Vs. Skin tests

Safe

The pricking or scratching process in skin tests is usually uncomfortable, and the resultant itching and swelling may prolong or become severe in some patients. Although the swelling usually disappears within 2 hours or less, prolonged swellings are treated with painkillers or antihistamine drugs. Some patients may feel dizzy after the test and need to lie down for a while. While skin test presents the above safety challenges, blood test presents none as it only involves the withdrawal of blood which is safe. For safety reasons, the blood test is used in patients suffering from skin diseases, severe anaphylaxis, and dermatographism.

Does not need a professional

While skin prick testing requires a health professional to perform the procedure and interpret the results, the blood test is direct and does not require any special experience, expertise or reagents for the medical practitioner performing the test. For skin test, the allergens need to be selected carefully by a doctor who will then perform the procedure, interpret the results and deal with any allergic reaction that might occur after the procedure.

No early preparation

The blood test is done without having to avoid antihistamine medications and drugs 3-7 days before the test unlike with skin prick test whereby using such medications 7 days before the test interferes with the test results. There is also no restriction on using creams and moisturizers which may cause further allergic reactions in skin prick test due to allergen extracts that they contain.