Linda is right on with this.Most vets only treat staph for a couple of weeks, when you need to treat for at least a month. If you have treated two or three times for a month, you may be looking at food allergies. Is he licking and chewing at his front feet? That is also a very common sign of food allergies. Common meat protein allergens are chicken and beef, tho a dog can be allergic to anything. Other common allergens are wheat, corn and soy. I really hope it is not a food allergy as they are a pain to work around.