After you take them to the vet many times and rule out any health issues I have tried a lot of things, with very little success. But not all enzymatic cleaners are created equal. As to the wet food, you might try the cheap stuff. There IS something wrong with your cat, sterile cystitis is often not simple to treat.
Help. My cat keeps peeing in the same spot.?
One of the most common reasons a feline will urinate in a spot that makes her owners cringe is illness. Wipe up the mess with a paper towel and then use a disinfectant and odor neutralizer. Does anyone have any ideas what is the best natural way to deter her as I can not take smelly sprays or aerosols. No data is shared with Paypal unless you engage with this feature. Was going to try the tinfoil but where she is peeing is directly in front of the litter box so I don't want her scared trying to get into the litter box. It's best not to change litters unless there is a problem.
How to Stop Cats From Peeing in the House | Animal Planet
To keep cats off and away from counters and furniture and anything else you don't want them to be, try using double sided tape for a week or two. Then use either or both! Her hiss we've become accustomed to; like a greeting or goodbye. I don't know what would have ever interrupted or upset her while she was using the litter box. It is possible due to her age and the dementia that could be the problem.