When your cat is being treated with a different dietary food for a different condition and also develops struvite, it is not recommended to just switch to a struvite preventative diet. Your veterinarian will decide if this is possible. The most important function of an anti struvite diet is lowering the urinary pH. When the pH of the urine is lowered enough, struvite stone formation will be prevented. It is also possible to lower the urinary pH by supplying specific supplements, like TROVET Anti Struvite | UAS. This way the cat can stay on the current diet and still have the favourable acidic urine. Always consult your veterinarian before treating your cat with acidifying supplements. When your cat suffers from kidney failure, acidic urine is not desirable.