Kate R has a problem with her cat, Arbus, who had to face an intruder not once, but twice. Kate writes:
Kate, the problem is that Arbus no longer feels secure in your home, so peeing in the house is most likely her attempt to feel better by spreading her own scent around. The physical tormentor may be gone, but Arbus still feels threatened because she can still smell the spray from the intruder cat. Cats have a much stronger sense of smell than us humans, and they make a lot of decisions based on the scents around them.
First, you'll need to determine whether or not Arbus has any health issues that are contributing to this behavior. For example, if she has a urinary tract infection, it may become difficult for her to hold it in. Your veterinarian will be the only one who can make this call. Since Arbus was "beaten up", it's probably a good idea to take her in for a physical checkup anyway.
We definitely believe that most pet cats should be indoor-only cats. If Arbus continues to be allowed outside, the chances are good that the intruder cat will assault her again and that fight could result in serious injury or death. In addition, not having a litter box means that you don't know her elimination habits. Stool and urination consistency are good indicators of health and they should be monitored.
Once you've eliminated illness as the cause, you can move on to other solutions. Whether you continue to allow Arbus to go outside or not, we suggest that you get an indoor litter box so that Arbus can have her urine scent present without soiling anything else. Arbus will benefit from it and she'll be more comfortable in her own home. Be careful to purchase a plain, open litter box and put it in an area where Arbus won't feel cornered. For more about litter and litter box choices, see this post.
Next, you'll need to make sure you clean every surface that was sprayed by the interloper. You can't always see or even smell where that was so you'll need to obtain a small black light. The ultraviolet (UV) light will clearly expose the areas that you need to clean. And don't stop indoors. Oftentimes other cats will mark exterior doors, walls, and even windows that they can jump up to, and Arbus will smell those markings.
To get rid of the odor completely, you'll need to wash it down with water and then use an enzymatic cleaner. Be sure to choose one that doesn't contain any extra ingredients that might harm Arbus. There are several of these sorts of cleaners on the market and most pet stores stock at least one. Do not use ammonia or vinegar as they will not effectively remove the odor and they could actually set them so that you'll never get them out completely.
The last step will be to help calm Arbus via scents you provide. Cats develop a communal smell between family members. That's why they rub up against you and lick their coats after you've petted them. They're creating their family's tribal scent. Try leaving an old pair of dirty sweatpants on the bed for Arbus to sleep on. Your scent will help assure her.
One last thing. Never, ever punish a cat for anything, but especially for elimination problems. Punishment only convinces a cat that you are no longer to be trusted. They do not see the causal link between their behavior and the punishment.
Kate, you clearly care for Arbus. We applaud your efforts to try and resolve her little problem. With a little luck and a lot of love, you should have Arbus back to her old, confident self in no time.