Question: How do I know that my child has outgrown a food allergy?
Answer: Well, we usually use three or four different methods to determine if a food allergy has been outgrown. The first is really asking carefully about whether there's been any accidental exposures, or in this case as you suggest, maybe an intentional introduction to see what happens. The intentional introduction is not something we would do first, though, because of the risk of potentially having a bad reaction.
The next methods we use are doing skin testing and blood testing to measure the level of allergy which may give us some indication of whether that allergy has been outgrown or not. And we've been very interested in this idea of the best method of determining which allergies have been outgrown and have determined that one particular blood test that's on the market is particularly good at giving information as to the level of allergy and being the best predictor of whether it may be time to try to reintroduce that food.
The last and final test is to do what we call a "food challenge test" where either at home, but more often under observation in my office, a family will bring their child in and eat that food under observation to see if they're still reacting or not. And we think this is not only the best method of determining whether the allergy is gone, but the safest way to reintroduce that food.