My own personal opinion of prescription diets is that they aren't formulated for
chronic conditions, whether for pancreatitis
, kidne failure or anything else. They really should really only be used for short-term, acute problems rather than a chronic illness.
Read the label on the prescription food and compare it to ingredients in other high-quality foods like Evo. If your dog does fine on a quality commercial food, that's great! If not, you'll need to supplement with vitamin tablets.