Skin problems are no fun. How long have the sores been there? Has he had fleas or been bitten by insects? Follow labmans advice for a while and like he said, if he still has problems, go to your vet. My puppy is currently on antibiotics and prednisone for an allergic reaction he had to fleas. Pain in the butt. He also had an allergic reaction to ant bites. Both times he had sores that got 10X worse with all the munching he did. The sores and irritation came from his allergies but as it turns out he caused the infection from all the messing he did with it. If simple grooming fixes the problem, all the better

Stop him from munching and licking as much as possible because that will only make the sores worse.