Royal Canin Urinary SO Adult Dry Dog Food is a veterinary-exclusive formula developed to nutritionally support your adult dog's urinary tract and bladder health. This kibble promotes a urinary environment unfavorable to the formation of both struvite and calcium oxalate crystals. It helps increase the amount of urine your dog produces to help dilute excess minerals that can cause crystals and stones. Relative Supersaturation (RSS) methodology is used to help lower ion concentration in urine. And with a reduced level of magnesium, the specialized formula helps dissolve pure struvite stones and prevent calcium oxalate stones from forming. Talk to your veterinarian about keeping your canine on Royal Canin Urinary SO Dog Food for long-term urinary support.