Royal Canin Veterinary Diet canine URINARY UC 18 LOW PURINE dry is a complete and balanced diet formulated to aid in the prevention and management of canine lower urinary tract disease due to urate, cystine, and xanthine urolithiasis in adult dogs. Moderate quantities of high quality proteins and controlled methionine and cystine levels help to reduce the formation of cystine stones while low purine proteins combined with the production of alkaline urine help to reduce the risk of urate stones. Enhanced levels of linoleic acid, zinc, and biotin help to promote a healthy skin and shiny coat.