Allergies? Help Please

Question
My dog (yellow Labrador) has had chronic ear infections treated with numerous antibiotics and cleanings. Only to come back again. He has has sores around his mouth periodically and his back left paw is sore and red. It seems to me he has an allergy, but to what. I mentioned that to the DR. she said we should put him on a special food diet and also told me to change his bowls (they are metal). Doesn't it seem as thought the symptoms are related? Is there any test that will isolate the allergy, rather than trial and error methods of different meds and expensive foods? I am all for buying my dog an expensive food if he needs it, but not for changing foods on him constantly if there is another way. Please help. I started with Science diet and have him on Nutro now. Thank you.

Answer
Food allergies can happen, but they are really rare.  More commonly, dogs are allergic to protein things in their environment such as pollens, trees, molds, mites, grasses, and the skin of other animals.  There are blood tests available to identify potential allergens. The tests do not identify food allergies!!

The allergy test I prefer is called the Allercept test from a company called HESKA.  Here is a link to their website that you might find helpful.  The test has to be submitted by your vet.

http://www.heska.com/Products/ALLERCEPT/ALLERCEPT.aspx