Leah,
I read your thread about Reece's latest trouble and I have been hesitant to comment, since you hadn't asked for any advice. But it seems like you would like a few comments. I am really glad that you are thinking along these lines. I know my doctor does skin testing around age 8. But they might do testing at a younger age if a child is having problems like yours. Especially for the more obvious allergies like pet, dust, chocolate, peanuts, strawberries, etc. And on younger kids they also do blood tests. They do elimination diets also to figure out the food part of allergies with the young ones.
There are a few things that you should be aware of. It is essential to identify allergies. At least you can avoid certain things. But even if you come up with a negative test, when you are hypersensitive (like CF people where chronic and acute inflammation is a problem) certain substances cause the same reactions as allergens. For instance, I recently spent a day in a park during what is the height of pollen season. I test negative for pollen. However, thirty-six hours later I had an excerbation. I was just sick for 2 weeks.
Things like pollen, smoke, pollution, fragrances, so many things can even cause a delayed reaction up to 48 hours later. So most people don't even make a connection. These substances instead act as a chemical sensitivities. These chemicals cause inflammation which can result in swelling and constriction in the airways which is the asthma component of CF. It is treatable and controllable. Which may mean less exacerbations. This has been my experience.
May I suggest that you read the recent thread on asthma? After reading about Reece's problems, I think it might be helpful to you to read up on some asthma, inflammation, allergy, and chemical sensitivity threads. If you are interested, I can direct you to some posts that may be helpful. I hate the thought of Reece being hospitalized when there may be some triggers that can be controlled. And if he has an asthma component, that he is on all available and appropriate medications which may require getting a second opinion. I say this because I was also being hospitalized and on IV's more and more frequently (with my FEV1 dipping to a low of 32%) until I found the right doctor who turned everything around.