When your dog itches, you know it. That relentless licking, scratching, chewing – anything he can do to relieve the itch. He seems obsessed, and he probably is. Whatever you do, don’t ignore this problem (as if you could!). Incessant scratching and chewing may indicate food allergy. He’ll constantly tear into any place on his body that he can reach with his teeth or claws. You may see ugly hair loss. Until you find the cause, this problem will go from bad to worse.