For the nutritional management of cats with struvite related feline lower urinary tract disease FLUTD FLUTD is a problem often involving the formation of mineralbased crystals and stones in your cats urinary tract that can cause a variety of painful symptoms including obstruction Struvite and oxalate are the two most common crystals that form in a cats urinary tract Prescription Diet sd cat food is formulated by veterinarians to help dissolve struvite crystals and stones in your cat Prescription Diet sd has low levels of magnesium and produces an acid urine pH to aid in the management of struvite crystals and stones The nutritional formulation of Prescription Diet sd may also be useful for pets with a variety of conditionsOther products from PetCareRx