Royal Canin Urinary SO for Small Dogs is a complete and balanced diet to assist the nutritional management of the following indications Small dogs 22 lbs with or at risk of developing canine lower urinary tract disease To help dissolve pure struvite uroliths To help prevent struvite urolithiasis To help prevent calcium oxalate urolithiasis To help prevent calcium phosphate brushite urolithiasis Contains nutrients to support oral health This diet promotes a urinary environment unfavorable to the development of both struvite and calcium oxalate crystals Increased sodium chloride content to increase thirst and promote formation of a dilute urine Restricted magnesium levels Restricted phosphorus and protein content Enriched with EPA and DHAOther products from PetCareRx