Biting Himself

by Wendy
(Barrie, ON Canada)

My JRT just recently started biting himself until his skin is raw. I haven't changed his diet and he's on advantage. I even flea bathed him just to be sure. Does any one know what it could be? I have been putting a bit of ointment on the areas that are red, and they seem to be getting a little better. If I can avoid a hefty vet bill with a simple treatment that would be great. However if I cannot get it to go away within the next two weeks I will take him anyway. I won't see him suffer. Please Help!