Thanks for the help. I'm not sure I can PM you, so I'll post here. We had an allergy test (ELISA blood test, although we do have access to more expensive skin testing) which came back only mildly positive for dust mites. I spoke with a neighbor who had a similar experience. The company who manufactures the tests is going to re-test during his worst season (late summer) for us hoping to get better results so we can give him allergy shots if possible. Dust mites can be controlled with cleaning and various products to render their "leavings" denatured. We talked about Atopica with his vet, but he's young and it's expensive and has some scary side effects. His worst problem seems to be foods, as far as I know.
We find some foods we can feed him, and then after a month or 2, he's breaking out in itch and rash and infection again, and tummy upsets.
First we used no meat for him, but it was too much fiber. Then we tried eggs -- allergic. Chicken and turkey -- allergic. No grains, even rice must be limited. He eats potatoes, but they don't completely agree with him. We've been giving him pork now. Allergic? Maybe. Or maybe it was the cat poop. I don't know how to stop the "allergic march" for him.
What kind of test did you have for your dog? Skin test, blood test (RAST or ELISA)? Was he having a lot of allergy symptoms when you had the test done? Kudos to you for going ahead with the shots. I hope they are successful!