Hill's nutritionists and veterinarians developed Prescription Diet® k/d®, clinical nutrition to support your dog's kidney health. The nutrition of Prescription Diet® k/d® is clinically proven to improve & lengthen quality of life. It helps Protects vital kidney & heart function. It also boosts vitality & energy. It supports your dog's natural ability to build lean muscle daily. This product requires a veterinary prescription. This product requires a veterinary prescription.