Very true. Food allergies are a common cause of chronic reoccuring ear infections. Although one thing you said was a little misleading. If a dog has a food allergy, switching to a premium food will unlikely make a difference. When a dog is allergic to the food, they are actually allergic to either a specific protein (usually beef, pork, or chicken) or a specific carbohydrate (such as corn) within the food. Since most foods (including premium foods) contain the same sources of protein and carbohydrates, you will probably see no difference. True allergy diets will contain alternate protein and carbohydrate sources such as Venison and Rice, or Duck and Barley, etc. Chicken and Rice Diets used to be very popular, but chicken has become so commonplace in diets nowadays, that it is often useless as a allergy diet.

To test to see if your dog has a food allergy, I recommend Science Diet z/d ultra. There is absolutely nothing in this food that the dog can be allergic too. Therefore it works very well to determine whether or not your dog has a food allergy.