Oliver looks like such a sweetheart and I am sorry he is having these bladder troubles![]()
Interstitial cystitis is something I have been suspected of having myself - it is a painful inflammation of the bladder lining and causes ulcers to form in there, too. You might read up on the human form via the internet - lots of info you may be able to try on a feline. At one time, I went to a support group and a drug they talked about as working *miracles* on the pain (for people) is Elavil - generic is Amitriptyline. I know that this drug is sometimes used for spraying kitties. It is very inexpensive and is also available as an ear cream for pets. It might be something to ask about. I am thinking that if you can relieve Oliver's pain - that alone might get him back into his litterbox.
As far as practical suggestions - it sure sounds like you are on the right track for trying things. Since the clever boy decided to try the human toilet - how about a completely different litter than you have ever used - like feline pine, crystals, etc??
Good luck to you and to Oliver![]()
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