Hi Rachel,
Before we get into your question, there is a great video we have “How can I stop my male cat from urinating outside of his litter box” where I address a similar problem that I encourage you to take a look.
Whenever our pets are eliminating inappropriately, whether it be urination or defecation, it can be caused by two things, medical reasons or behavioural reasons. So the first thing we have to do is rule out medical problems. It helps that you have worked with your veterinarian to resolve some medical questions. You did not mention if blood tests were done or if early signs of arthritis may have been noted on the X-rays. Otherwise, the behaviour aspect must continue to be investigated or addressed.
Cats are very in tune with their environment and so there are many stimuli that can cause them to become anxious or change their behaviour. Cats can also perceive things that we can’t, so a high-pitched sound that doesn’t bother us, may bother them and cause them to be fearful around the litter box. Now you may go hunting for these things, but in the end, it’s rare to find. It doesn’t take much for a cat to start eliminating inappropriately and once they do, the reason they started doing it may be gone but they are now just continuing. The longer you let this go on, the more it’s going to be ingrained and difficult to resolve.
There are some strategies you can employ to focus their attention on the litter box. You can start putting treats near the litter box but I always tell people not to let the cat know you’re putting them there. This way they just happen to find them there. They may start visiting in the litter box just to see if they’ve shown up again and since they’re there, they might as well use the litter box.
If you haven’t added a second litter box to the home, it’s definitely time. Keep in mind that cats can develop issues like arthritis, which can make it difficult for them to go up and down the stairs and this may be the cause of not visiting the litter box. I encourage you to take a look at our video “Signs of Arthritis in Cats and Dogs & 4 Key factors to Prevent Lameness or Stiffness” in case of the condition.
When a cat is really overweight and large, they may no longer fit in the litter box and it may not be comfortable to use it. I often have owners buy a large bin, cut the sides really low, put it in a garbage bag and sprinkle litter on top of it creating their own litter box with a much larger surface area and low sides to it so it’s very easy to step in and out.
There are also products that you can sprinkle in the litter that is supposed to attract them to it. These can work in some cases but not in others.
If anxiety is the cause, you may be able to improve this with environmental enrichment. Get your cat playing more and engaging it with toys. This will reduce stress. If your cat is overweight, this alone can make it stressed so focusing on weight loss in cooperation with your veterinarian would help as well. I would recommend you to take a look at a video “Preventing Obesity in Pets” for more information on this specific topic.
Since your cat is eliminating in a particular spot, you can restrict access to this area if possible. Always clean the area where they have eliminated very thoroughly. Even a small amount of debris or odour will make them return to that place and think it’s an appropriate place to eliminate.
Lastly, a lot of cases do take medication to solve these issues. I would have to say that anxiety, in general, is usually the cause of the problem. Whenever I say this to clients, I always get the same response that their cat is not stressed. But what clients don’t understand is that although you’re providing a very nice home for your pet, we have to remember that these were animals that lived in the outside environment and engaged with their world by hunting and hiding. Many cats can develop stress just by being an indoor cat. You can speak to your veterinarian about anti-anxiety supplements and anti-anxiety medication to use as a trial if the aforementioned strategies do not work.
If you reach an end and are considering euthanasia… and I only say this because I have seen it before, I’m not making any assumptions but I just need to make the point. You could consider drastic measures, such as restricting your cat to a small room or small area of the house, give them anti-anxiety treatment so they are not stressed about that, and give them very little choice other than to eliminate in a litter box. I must stress that this is as a last resort before giving a cat up for adoption or making them an outdoor cat which in itself can be quite dangerous and still may not fix the problem when he is in your home.
I hope this helps,
Dr. Ryan Llera