Why Do Cats Pee in the House? Part 2: The Veterinarian’s Perspective

Cats are probably where the term “pissed off” originated

Published: January 15, 2018

Poor Phyllis. And poor Dickens.

The problem Phyllis mentions – inappropriate elimination – is unfortunately not an uncommon one. Although I usually work in the ER where we don’t often have to deal directly with it, it’s usually seen by general practitioners and veterinary behaviorists.

Cats and pee. Dogs do it as well, and it’s not always just urination (“Honey, why is there poop in the living room?”), but cat pee is such a pernicious and foul substance that it deserves special attention. For now, let’s focus on cats. Of all the variants of species and bodily effluents possible, a cat peeing outside the litter box is the most common form inappropriate elimination takes.

The causes fall into two general categories: medical and behavioral. I'm prepared to deal with the first one, and totally out of my element with the second one. The job of most general practitioners (GPs) is to rule out medical causes for cats who chose to pee outside the box, and then get the cat to a behaviorist to settle the mental causes. (The veterinary behaviorists at VIN often recommend reading the Ohio State University College of Veterinary Medicine's Indoor Pet Initiative.) However, many GPs, either because they like behavior or have clients who won’t or can’t see a behaviorist, also end up tackling the behavioral part of the problem.

Before I embark on medical reasons, let’s explore the toll that this can take on the relationship between a cat and a family, and a few easy steps to consider when faced with this pee problem.

As I said, cat pee is a horrid, awful, yucky, no good substance. There’s a reason cats use urine to mark territory: it smells (with a capital Stink) and it sticks around. It’s awfully hard to get the smell out. The smell of cat pee tells them there’s a bathroom around here somewhere, so a good clean-up is vital to remove that cue and direct them to the litter box. Phyllis is lucky to have landed on a product that helped her rid her home of the smell. Many pet owners are not so lucky; if they have a cat who inappropriately pees around the house, they may come home every day to a house that smells like a zoo. It’s that bad. Stink…stank…stunk.

Over time, that smell tears at the fabric that holds the relationship between pet and person together. I have been asked many times to euthanize cats that are ruining clothes, carpet and furniture. Some of these families have tried many things to get the problem to stop and are at their wit’s end, while some (perhaps suspecting that it’s oftentimes a losing battle) arrive at this conclusion without trying anything. I always try to find an alternative, such as a medical workup or referral to a behaviorist, but I have agreed to it several times over the course of my career. Much like having an aggressive dog, a cat using your house as a bathroom can lead to a life-or-death situation. It’s a deal-breaker in most cases.

First, the easy stuff. Male cats, especially male cats who have not yet been neutered, have a biological drive to mark their territory, and they are armed with an effective weapon for doing it. Neutering is the first step when dealing with any intact (un-neutered) cat who is urinating outside the box. It’s simple, cheap and effective in most cases. Some cats and dogs who are neutered late may already have developed a habit of marking, so neutering young, say before sexual maturity – about 6 months - is important.

Next up is the litter box. If given the option to relieve yourself in a nice, clean tile-lined bathroom or the grungy restroom of the local dive bar after the Superbowl, which would you chose? I thought so.

Ditto the litter box. If your litter box hasn’t been cleaned since the Carter administration and is piled high with soiled litter, you can be sure that your cat will opt out in favor of something like Phyllis’s nice, tidy pile of laundry. A clean litter box is an invitation to use it, and one heaped with pee biscuits is a big warning sign to your cat that says “Stay Away!” Keeping a scrupulously clean litter box is right up there with neutering in terms of importance and ease. It should be scooped out every day, periodically washed and have a litter type that your cat likes. Some cats who are peeing in the house do so because they just don’t like the litter. Maybe they hate clumping litter, but would be okay with pelleted newspaper. Even the type of box can affect their decision to use it or not; some cats like the enclosed kind, for a little added privacy, while others prefer the open-top model. Dickens has three litter boxes all to himself, with his two favorite litters as determined by a litter buffet.

Litter box placement can also be a factor. If your litter box is placed right next to the washing machine, maybe your cat is terrified of the metal mechanical beast that makes really scary sounds. A secluded spot for reflection and a quiet pee may be just the thing (when coupled with litter box design and the right litter) to correct the problem. Easy pee-zy.

So, what medical conditions will cause a cat to do this?

Here’s the short list: Stress, infection, stones, tumors and a perplexing disease that’s “none of the above.”

Stress is a biggie. Cats are very probably where the term “pissed off” originated. When upset by whatever factor displeases them, they take to urinary graffiti to show us. New cat in the house, new human in the house, new house…all can make Dickens decide that Phyllis’s living room rug is the new hot spot to relieve himself. If the dog or kids can corner the cat in the litter box, or block them, that’s stressful. Cats need to feel safe when taking a whiz.

One way to combat stress (assuming kicking the new human out of the house isn’t a viable option) is to use the power of pheromones. Pheromones are airborne chemicals that cats use to communicate, and some smart people have decoded the pheromones cats use, which are secreted by glands in their cheeks, and bottled them. The most convenient form is a plug-in version that disseminates stress-soothing pheromones through the house (without any smell detectable by people). It won’t work for all cases but it’s a low-tech and low-cost way to help. Anything you can do to de-stress your cat’s environment will also help.

A urinary tract infection (UTI), while somewhat rare in cats, can also make them take to peeing outside the box. Don’t be confused and think that ALL cat urinary problems are caused by infection (more on this below), but it can happen. If you see blood in the urine or the cat is straining to urinate, a UTI could be the culprit. This is where we veterinarians come in; a urinalysis obtained by cystocentesis, which involves inserting a needle into the bladder to get a sample not contaminated by the lower urinary tract, is the best way to get a urinalysis and culture. Just “trying” antibiotics to see if they solve the problem is not a good approach, though many owners may want to in order to skip the diagnostic costs. The overzealous use of antibiotics has allowed many bacteria to develop resistance, so it’s worth getting the sample and doing it right.

A cystocentesis, although it sounds scary, is a simple and nearly painless procedure. It’s not 100 percent risk-free (nothing is, really), but it’s commonplace enough that any veterinary hospital can do it safely.

Seeing blood in the urine can sometimes be a sign of an infection, but many other conditions can do this. Cats with a UTI may also urinate on surfaces that highlight blood, like the white surface of a tub. If you see bloody urine, it’s time to see your vet for some tests. If your cat has a UTI confirmed through testing, a course of antibiotics, guided by a culture telling us what antibiotic is best, can be a simple fix.

Stones in the bladder or elsewhere in the urinary tract (sometimes called kidney stones, which is only accurate if they actually reside in the kidney) can lead to irritation and pain. Much like it happens with stress, a cat with a bladder full of stones is prone to letting you know he doesn’t feel well by peeing in odd places. Sometime crystals from the stones can show up on a urinalysis, but crystals alone aren’t enough to tell us if there’s a stone. Plus, some stones don’t show up on X-rays. I have seen stones aplenty removed at surgery that were invisible on an X-ray. If you or your vet suspect stones and a urinalysis and X-ray don’t yield answers, an abdominal ultrasound is the best way to detect them. Stones can hide from X-rays, but all will show up on ultrasound. For most stones, surgical removal is the first step in determining type of stone and the best way to prevent them. In most cases, a specific diet will greatly decrease the recurrence of stones, although there is always a risk of reforming them. In some cases, a diet change will cause some stones to dissolve, but most cases need an initial surgery to remove and identify them.

Tumors in the bladder or urethra can mimic stones and infection and are another cause of inappropriate urination. Bladder tumors almost never show up on regular X-rays, but can sometimes be detected with special X-rays using dye or air as a contrast medium. Ultrasound is also a good way to find tumors in the bladder. Surgery, chemotherapy and radiation are the three main ways that bladder tumors are handled, but a biopsy (usually obtained at surgery) is the first step in identifying the tumor type and coming up with a treatment plan. The bladder is quite forgiving at surgery; you can remove most of the bladder if needed, if there’s large tumor, and the remaining portion will handle the job.

And now we come to the final mysterious condition that can cause cats to pee in the house. It goes by many names, and the names keep changing. Thirty years ago, it was called feline lower urinary tract disease (FLUTD) and in the ensuing decades it’s gone by feline urologic syndrome (FUS), feline interstitial cystitis (FIC), and the rather fanciful Pandora Syndrome. All these name changes highlight two main points:

1) When a cat strains to pee (or in some cases, has a urinary obstruction – male cats in particular) many things can cause it – it’s not really one disease.

2) We really don’t know how to best diagnose and treat it. Crystals in the urine, phosphorus in the diet, stress – all have been implicated in causing “it” but addressing each of these factors has unveiled yet another thing that might be the culprit. Surely, next week it’ll be grain in the diet or stray moonbeams that are the causative factor.

Cats with this condition (I prefer the FUS acronym) mimic cats with tumors, infection and stones but none are found during a medical workup. Cats with FUS pee all over, they get life-threatening urinary obstructions but diagnosing and preventing this disease are exercises in frustration. Often, pet owners and frustrated veterinarians will say “Oh, my cat had a UTI” because that’s something you can get your head around, but that’s not often accurate with FUS cats. The biggest factor that’s got some science behind it is stress, so all the points above regarding stress come into play with FUS, but that’s not often enough to fix it for good. It’s an exhausting and frustrating dimension of an exhausting, frustrating and potentially deadly disease.

If I had to venture a guess, I’d say Phyllis’s cat Dickens is one of the stress variety of pee-ers, since that’s a common and consistent trigger for this problem. For other cats turning their owner’s house into a pee palace, the best place to start is a visit to the vet for a workup, and a referral to a behaviorist if nothing medical turns up and the easy stuff doesn’t fix it.


Kyra Peters
February 21, 2018

I really didn't know that

Dr. Tony Johnson
February 21, 2018

Hello Marla; If you are using the term "UTI" to mean any inflammation in the urinary tract, you are correct. The term UTI technically means infection, and most cases of feline urinary disease are sterile, so the word infection does not apply in about 95% of them, but inflammation (which is different from infection) surely does. The terminology can be confusing, and even many veterinarians use the catch-all term "UTI" for conditions in which no bacteria can be present, so I can understand the confusion. But most cases have no bacteria present, so antibiotics are not needed - and only contribute to increased bacterial resistance and other problems, such as diarrhea and loss of the normal gut bacteria that are needed for normal digestion.  Thanks for your feedback. Sincerely, Dr. Tony

Marla Faulkner
February 20, 2018

as a responsible breeder, MOST of the time is because of a UTI. Bring you cat in to the vet to be tested and is usually the case results will point to a UTI.

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