There are two main brands of veterinary specific diets which support diseases in dogs and cats, these are Hills and Royal Canin.
For sterile cystitis, these foods are called Hills C/D Stress and Royal Canin Urinary Calm. Both are essentially very similar in terms of how they support your cat with stress cystitis. Most importantly, the food helps by promoting desirable urine pH levels which are less irritable to the bladder and contains ingredients to help manage stress.
Now I’m going to show you the difference between the brands of stress cystitis food available and the flavours. I would offer to try the foods myself but I’m not stupid so, instead, I’m going to use Milo as the taste tester!