Recent improvements in laboratory techniques have made blood testing for food and airborne allergens more reliable than they previously were. The test should include both IgE and IgG antibodies in order to identify both immediate and delayed type allergens.
Good laboratories for this kind of testing can be found on our links page. Before having your blood tested, be sure to include any food you are suspicious of in your diet. The lab test may not indicate a reaction if you are not currently consuming that food.
There may be other restrictions required depending on the type of test you will be doing. Your doctor will know what these are.
While an elimination diet is less expensive, it is more cumbersome and may result in confusion or discouragement, particularly in children.