Why is My Cat Urinating Outside the Litter Box

Inappropriate urination, when cats urinate anywhere outside the litter box, is an incredibly frustrating issue. Cat urine has a very strong smell, and if not cleaned appropriately can leave a lasting odor or stain.

So what would trigger a cat to urinate on the carpet or clean laundry? Some people think their cat is mad at them or being a jerk. It’s actually more complicated than that.

Cats may urinate outside the box for either medical or behavioral issues.

First let’s go over some of the potential medical causes, how they can be diagnosed, and how we may treat them.

1. Infection

Although rare in male cats, bladder infection could be a potential reason your cat is urinating outside of the box.

One thing we have learned from cats is that when it hurts to urinate or defecate, they will often associate that pain with their litter box. This means they will develop an aversion to the litter box and will start to urinate elsewhere.

I discussed urinary tract infections in dogs in another post, but the testing is similar for cats. We will usually run a urinalysis first and if bacteria are seen under the microscope, this means there is an infection. A urine culture is then the best test to figure out what kind of infection your cat has and which antibiotic is best to use.

Typically if you cat has a bladder infection they will experience pain when urinating, but be otherwise normal on exam. Unless the infection has spread to the kidneys they should also have normal bloodwork.

But because it burns when they urinate they will often stop using the litter box. Many times clients will report their cat urinated right in front of them. It’s possible these cats are trying to show their owners something is wrong. But many times these cats are just urinating much more frequently so the owners catch them in the act more easily.

Unless the issue has been going on for such a long time that they have formed a new favorite place to urinate, there is a good chance your cat will start using their litter box again after treatment with antibiotics.

2. Crystalluria

When we perform a urinalysis we are also looking for abnormalities other than infection. One of the things we check is the pH of the urine.

A normal urine pH should be between 5.5 to 7.0 When the urine is too acidic (less than 5.5) or too alkaline (greater than 7.0) this can cause different urinary crystals to form. These are not stones that can be seen with the naked eye. But microscopic crystals that can only be seen under the microscope.

Despite their small size they can still cause a lot of issues. The crystals can cause pain and inflammation while urinating, similar to symptoms of a UTI. But typically these cats do not have an infection.

The ideal treatment is a prescription veterinary diet designed to neutralize the urine pH so it falls back into the range of 5.5-7.0. The reason this helps is because the two most common types of crystals in cats do not form as readily when the urine is within the normal pH range.

The other thing these diets do is to dilute the urine. Most cats do not drink enough water, and very concentrated urine will mean a higher concentration of crystals. The diet dilutes the urine which promotes better bladder health. Some prescription diet options your veterinarian may recommend are Royal Canin SO, Royal Canin SO + calm (which contains additional ingredients to reduce stress), and Hill’s c/d.

Untreated crystals can also lead to more serious issues in male cats if not treated. Male cats can develop a life threatening emergency called a urethral blockage. Because they have a very narrow urethra (the tube that allows urine to exit the bladder) it can become blocked very easily.

When this happens they can not urinate at all! The bladder gets big and very firm. Kidneys values will become very elevated because the kidneys can no longer excrete them through the urine. And potassium will also start to elevate. When it becomes too high this can cause the heart to stop.

The treatment requires sedation or anesthesia and placement of a urinary catheter. Ideally, I like to leave this catheter in place for 48 hours while keeping these cats on IV fluids to allow diuresis and flush out the elevated kidney values. But there are some other protocols being used by many veterinarians which shorten this treatment plan in order to save money.

These protocols usually involve shortening the time within the hospital while using aggressive medical management at home to prevent these cats from re-blocking. It can be effective, but if it fails the cost could be even higher if another urinary catheter needs to be placed.

3. Feline Idiopathic Cystitis

This condition has gone through some name changes over the years. When I was in school it was called FLUTD (feline lower urinary tract disease). It is a chronic condition characterized by painful non-infectious inflammation of the bladder.

It typically occurs in young to middle age cats that are less than 10 years of age. Male cats may or may not be more pre-disposed, but they are definitely at greater risk of developing a urethral obstruction from this condition.

When they develop an obstruction from FIC it is typically due to a “plug” of mucus formed from white blood cells.

This is a very complicated condition which we are still learning more about. These cats suffer from multiple hidden issues which causes chronic painful inflammation of the bladder wall.

One issue is they have abnormalities to the bladder wall itself. Their bladder wall is more sensitive to stimuli, and may have a “leaky” inner wall which allows the urine to stimulate the nerve receptors and cause pain.

Some treatments are being used which may improve the strength of the bladder. One of these treatments is the use of glucosamine supplements such as Cosequin as it may help improve the health of the bladder wall.

Another treatment is the use of pain relief to counteract the pain and heightened nerve signals these cats have. I have used both buprenorphine (an opioid) and gabapentin for these cats.

A newer medication that has been used is called Cerenia (maropitant). This is a drug that is labeled for and primarily used to prevent vomiting in cats and dogs. But we have found that it has some excellent anti-inflammatory effects. We are also using frequently for chronic coughing or sneezing.

Cats who suffer from chronic cystitis also tend to be more sensitive to stresses and changes in their environment. Small changes to their routine can trigger a bout of cystitis for these cats. For this reason anti-anxiety and anti-depressant medications are also frequently used to manage these cats.

Just like in people, every cat responds differently to different anti-depressants. So it’s just a matter of finding which one works best for each patients with the least side effects. The ones used most frequently are fluoxetine, amitriptyline and clomipramine.

Reducing this increased stress and anxiety in these cats can be life changing.

In addition using over the counter products like Feliway can reduce their stress and decrease the frequency of episodes.

We have also found that environmental enrichment can play a major role in improving their happiness and quality of life.

One thing that can help is feeding canned food daily. It not only increases their water consumption which helps dilute the urine, but it has also been found to improve the bond between cat and owner. A stronger human animal bond will mean less stress for these cats.

You should also provide toys and elevated perches for them to rest. You can now find several affordable cat trees on Amazon.

The Ohio State University Indoor Cat Initiative is a website with extensive information on animal behavior and ways to provide enrichment in your home.

Although the chronic cases are the most severe and difficult to manage, any cat can develop cystitis if their environmental stress is strong enough to trigger inflammation.

My own cat developed cystitis with bloody urine after receiving radioactive iodine to treat hyperthyroidism. This treatment will make cats radioactive for a couple of weeks while their body excretes it from their body. This meant I had to use flushable litter because you don’t want to put their radioactive urine or feces in the trash can.

I set my cat up in a room with his own litter box and bedding to try to keep things contained and safe for my family. This also meant he wasn’t allowed in the backyard which had been his routine.

Everything combined was just too stressful for him and he began urinating outside the box with blood tinged urine.

But since then he has not had any other episodes of cystitis. So he is not a typical FIC cat, but with enough stress he did develop symptoms.

4. Systemic Diseases

Sometimes cats begin urinating outside the litter box due to diseases which cause increased volumes of urine. The two most common causes are chronic kidney failure and diabetes mellitus.

These cats will start to urinate larger volumes of more dilute urine. They will also start drinking more to replace the water lost through the urine. So if you notice you are scooping larger volumes of urine out of the box, or your cat is suddenly drinking larger volumes of water, you should seek veterinary care and bloodwork.

These cats usually will continue to use the litter box, but it is possible that they will need to urinate before they can make it to the box. This is more likely if they live in a large space where the box is farther away.

5. Arthritis

As I mentioned above if a cat feels pain when urinating they may associate that pain with the litter box. Their response to this is often to stop going inside the box. Cats with arthritis may feel pain when they squat down, so will choose to not use the box anymore.

If you have a very large box they also may struggle to get into the box. A smaller or more shallow box may help.

I discussed arthritis treatment in detail in another post on this site.

Now let’s go over the other cause for inappropriate urination, when all of the medical tests come back normal.

Behavioral Inappropriate Urination

This is also a complicated issue with multiple potential causes. Cats are finicky creatures, and will have unique likes and dislikes.

Sometimes cats will stop using the litter box because they have an aversion to something associated with the box. This could be the type of litter. Some cats want fine particles and some prefer large pellets.

They can also be picky about the litter box itself. Some like a large open box while others prefer it to be covered.

The location of the box is also important. Most cats do not like for the box to be near where they eat. And if the box is in a noisy location this can startle them and cause them to stop using it.

Other times cats will start urinating in a different location, not because they dislike their box, but because they have found a new place that they just like much better.

They may like that the bathroom mat or the clothes in the laundry basket are soft, and prefer this location to others. In this situation it’s important to close off their access to this location and try to make the litter box more enticing.

There are also some “rules” with litter boxes. The number of boxes should equal the number of cats + 1. They should also be spread out and occupy every floor of the house. Behaviorists have reported going in to the homes to evaluate why a cat is urinating outside the box. And sometimes they discover that the “problem” cat is actually being kept from having access to the box by another cat who is blocking the way.

It is important to keep the boxes clean. Some cats will simply not use a dirty box. So it should be scooped daily and cleared out completely every couple of weeks. I also try to scrub the boxes with dawn every couple of months before putting in new litter.

If you hate scooping litter boxes you could consider purchasing one of the automatic cleaning litter boxes such as this Scoopfree product from Amazon, or the very pricy but highly reviewed litter robot.

Your vet has now ruled out medical reasons for why your cat may be urinating outside the box, and you have corrected any environmental problems such as location or incorrect number of boxes. It is time to start looking at other ways to fix the issue.

If you feel confident that your cat does like the type of box, litter and location, then you can try luring them back to the box with something like cat attract found at Chewy. These products contain herbs which are tempting to cats and can be mixed in with the cat litter.

You can also use products like Feliway to reduce stress. Be sure to plug in enough of these to cover the square footage of the main living areas that your cat uses. The pheromone scent in the Feliway product will create a sense of calm which may decrease the number of incidents.

You also need to be sure to clean the locations where your cat has urinated correctly. 
This means using an enzymatic cleaner like Nature’s Miracle first. Once this product has fully deodorized the urine smell you can then clean the carpet or rug as normal.

If you don’t use a product designed to break down urine particles, you may be left in a situation where your cat continues to go in that spot because they can still detect the urine smell from before. This makes it much harder to get them re-trained to use the litter box.

Additionally in severe cases your vet may prescribe an anti-depressant such as Fluoxetine which has been found to reduce inappropriate urination in cats.

Even cats without cystitis can also benefit from environmental changes such as increasing water intake through canned food. As I mentioned above, feeding canned food is found to increase the human animal bond and can reduce stress and behavioral issues.

Whether it’s for medical or behavioral reasons, having a cat who is urinating outside the box is a very frustrating issue. It can also be a frequent cause for cats being surrendered to a shelter or even euthanized.

If you are dealing with this issue please don’t wait to seek help until you are at your limit of patience. Use this guide, and the resources linked in this post, to institute some environmental changes.

Also schedule an appointment with your veterinarian so they can perform a physical exam and urinary testing to determine if there is a medical reason for your cats issues.

And if it reaches a point where anti-depressant medications are recommended, keep an open mind! I have used fluoxetine in my own cat for a different behavioral issue and it helped her tremendously during the six months after my first child was born. I also was able to get it compounded in to a chicken flavored liquid formula which made administration much easier.

First let me say that I am so sorry if you are dealing with this issue. I know how frustrating it can be. I hope this post has helped provide some information that may help you and your own cats.