Hello I am Dr. Joey. Thanks for trusting me to help you and your pet today. I am a licensed veterinarian with over 16 years of experience. I look forward to working with you.
This can be a very frustrating problem! For any older cat with this type of problem the first thing I always recommend to my clients is to give him the benefit of the doubt. He could have a medical problem such as urinary tract infection, poly/tumor, crystals in the urine or bladder/kidney stones or even kidney/liver issues. Therefore, it is very important you have your veterinarian do an exam followed by some lab testing that includes lab work (CBC, chemistry profile, thyroid screening and urinalysis) +/- imaging (ultrasound or X-rays) to make sure. We must keep in mind dementia and there are some newer medications that people have been working with that help a little bit (if you want more info on this let me know and I can discuss this further). Unfortunately, this sounds very behavioral since he does not do it all the time and focuses on particular piece of furniture. As a behavioral issue there is no way to sugarcoat this...this will be tough to combat. But I have a few suggestions for you.
First, we must assess the litterbox situation. Do you have enough litterboxes? The recommendation by specialists at this point is that you have one box per cat plus one. If you have one cat, you should have two boxes. This is just the recommendation out there by veterinary behaviorists and internal medicine specialists. Some cats are extremely territorial about their box and may prevent another cat in the household from using the box. An especially fearful cat may not approach a box because something terrifying is between him and the box, such as a vacuum cleaner. Therefore, he will eliminate outside the box instead of approaching it. With two boxes, the problem is solved.
Where is the litterbox located? Cats don’t like to have their litterbox close to their food or bedding. They like to have a consistent, private place to do their business. So, don’t put the box in one of the busiest rooms in the house. Be careful with boxes in the bathroom. If a cat gets sprayed by the shower while eliminating in the box, you can be guaranteed he may refuse to use the box again. Is the box easy for the cat to get into? This may be silly, but some people keep the boxes in a closet and then forget to leave the door open!
I always like to assume you are doing a great job with cleaning the box (scooping all daily; cleansing out the litter entirely every 3 to 4 weeks and when you do this complete change-out you actually cleanse the box itself with a non-ammonia cleaner). I recommend try a different litter type. Try one that isn't as dusty and doesn't have an overt odorizer. For example you can try either "World's Best Cat Litter" or "CatAttract". I've had a few clients with success with either one of these.
I think I forgot to mention above that if you have a hood on the box, take it off at least for now. Some cats dislike the gas chamber effect they create. Other cats that are arthritic or on the larger side have a super tough time maneuvering into/out of the box to go, and ultimately give up and go near it. If you feel like it is a smaller box and one of the offending cats does have arthritis, then perhaps try a larger box that he can maneuver around in. Some people buy one of the tupperware containers that is a low rectangular box and cut an entry-way into it. This works superbly. Our goal is that we want all the cats to love their boxes. We want them to jump in there, scratch around and make a big mess which means they likes being in the box.
Some cats need to be confined to a smaller area for a while until they earn the privilege to get back into the whole house by proving they can consistently use the box. You should not feel guilty about confining all or just the offenders to 1 or 2 rooms for a few weeks until they prove that they are able to do this. During that time you can make the litterbox an excellent experience as noted above. Also we can work on reducing anxiety since this can sometimes play a role in these problems. If not already tried, buy a Feliway Diffuser or Feliway Spary. This releases the positive cat pheromone that makes cats feel awesome and are less likely to misbehave (can't hurt and might help). If you have the spray, cleanse the area he urinates thoroughly (products mentioned below) and then spray this area. Spend quality time with each cat daily doing what he likes whether that be petting, brushing, playing (laser pointer chasing, feather on a pole chasing, retrieving, etc) for at least 10 to 20 minutes a day. This helps him know you still care. If you already do this, then you are one step ahead of most to help him.
As some final notes, be sure not to punish the cats when you find the disasters. I know it is our first instinct, but this only serves to increase anxiety and can worsen the situation.
The other thing it is very important to thoroughly cleanse all areas that a cat has inappropriately eliminated. I recommend using an enzymatic cleaner such as UrineAway or UrineEase. These can help get rid of the odor. If you have carpets, steam clean. If the cat smells it, then he is more likely to go again in these areas...plus it improves the odor for your nose as well.
Cleaners that work:
URINE OFF - there is a formula for dogs and one for cats
Odor removers (to use after cleaning):
Elimin Odor Feline
Cat-Off Odor Concentrate
The list isn't long but that's it. They work. You will read many online that use some of the natural easily available products like Nature's Best, ***** ***** this product like many is very sensitive to temperature and can be affected by other cleaners that you use. So, I can't recommend it.
Finally, if all this fails or you have already done ALL of this, then you need to speak with your veterinarian about medication to reduce his anxiety. WE have many options and ways the drugs can be compounded to make them easier to give.
I am at a point I need to know what questions you have. I hope that the information I provided has been helpful.
Please let me know if for any reason you need further clarification, have more questions, or were expecting a different type of answer.