Veterinary Diets Purina EN Gastroenteric Cat Food 10 lb This diet promotes a urinary environment unfavorable to the development of both struvite and calcium oxalate crystals This diet promotes a urinary environment unfavorable to the development of both struvite and calcium oxalate crystals High protein & low carbohydrate to help support gastrointestinal health High total digestibility to promote nutrient absorption All Natural. No Corn, No Wheat, No added artificial colors or flavors