Royal Canin Urinary is for the nutritional management of bacterial cystitis, dissolution of struvite uroliths and management of recurrent struvite and calcium oxalate urolithiasis. Urinary S/O effectively dissolves struvite uroliths. An acidic urinary pH is unfavourable to the development of bacteria, which are frequently associated with struvite uroliths. Diluting urine decreases the urinary concentration of struvites and calcium oxalates. The larger urinary volume also ensures regular bladder wash-out. Undersaturated urine is an environment where crystals cannot proliferate. Thus the urine is unfavourable to the development of both struvite and calcium oxalate crystals. Magnesium is a component of struvite (magnesium ammonium phosphate) uroliths.