Pet Talk

Dr. Kenneth Geoghegan, of Village Veterinary Hospital in Warson Woods, has been a neighborhood veterinarian since 1992. For more information visit

Nothing is worse than a house reeking of cat urine. You may recall visiting your Aunt Sylvia, the one with five cats and one litter box, which seemed mysteriously dry. You may also remember pinching your nose to avoid the unmistakable stench of feline urine. This is known as inappropriate urination, urinating outside of the litter box.

There are many causes of inappropriate urination. Most seem to based in behavior, but a good percentage can be medical in origin. Decades ago, it seemed that every case was about ‘Frisco’ being upset and taking it out on the couch cushions. We would assume it must have been a behavioral problem. Further investigation often reveals an organic underlying cause. Let’s explore some of these causes, albeit in an over-simplified form.

Diabetes mellitus is almost always diagnosed because of the inappropriate urination that accompanies it. Cats with this common form of diabetes urinate a lot. Symptoms appear acutely, accompanied by an enormous thirst; the two go hand and hand. Owners find themselves apologizing for scolding their kitty after they discover that diabetes caused the urine in the bed. 

Sometimes when a pet has a medical condition, especially one that can cause symptoms of increased urination, or polyuria, like diabetes and kidney disease, the cats can’t help themselves. They gotta go, litter box be damned! Which brings up kidney (renal) disease. Seen most often in older cats, kidney disease causes polyuria and a concomitant increase in drinking, or polydypsia. The increase in urination is due to the failure of the kidneys to concentrate/dilute/ filter correctly.

Failing kidneys may manifest symptoms in two ways: acutely or chronically. Acute renal failure happens, by definition, very quickly, resulting in one sick kitty. The scenario for chronic kidney failure is more insidious, as it occurs over time. A cat can seem perfectly normal while the kidneys fail unbeknownst to the owner. As the failure progresses, the cat’s ability to compensate for the loss of kidney function wanes. When the ratio of functional kidney to failing kidney tilts past 30 percent/70 percent, respectively, on comes the polyuria. The cat can urinate so much as to become dehydrated, resulting in increased drinking (polydypsia).

Other medical conditions may result in inappropriate urination, too, conditions that have little or nothing to do with the urinary tract. A cat may know there is something wrong and urinate outside the box because of stress or uncertainty! It could be cardiac disease, thyroid problems or even dermatitis, the cause doesn’t have to be related to the cat’s plumbing. I am convinced cats will urinate all over your house to tell you, “Hey, something is wrong with me!” especially if they do it right in front of you. Time to go to the vet.

The No. 1 cause of inappropriate urination is a bladder infection, with or without crystals in the urine, or ‘stones’ in the bladder.  Most cat owners are too familiar with these conditions. They are most often dismissed as behavioral because they can be intermittent, chronic and recurring. There is great debate among the experts regarding feline lower urinary tract disease, but that is not the purpose of the discussion here.

Bladder infection symptoms mean pain, blood in the urine, increased frequency of urination, straining to urinate and inappropriate urination. Bladder infections can be complicated by ‘stones’ in the bladder, and/or crystals in the urine. Cats often associate the pain of urination with the litter box, and thus avoid it. They may push and push to go. This straining is the result of an irritated bladder wall telling the brain that the bladder is full, when indeed it is relatively empty. You may find multiple small puddles around the house if a cat is suffering from a bladder infection. The worst complication, which results in an emergency situation, is a cat (most often male) who becomes urinary-obstructed with those crystals, or has mucous plugs in the urethra.

When there are mishaps outside the litter box that are behavioral, they often relate to a cat’s environment. For example, the number of cats in a household can be a factor, as can the number of litter boxes. Generally the rule is one for each cat. The environment around the litter box can also be an issue. I once saw a cat who was inappropriately urinating, with no real medical issue. He refused to go into the small space where the box was because that spot was flea-infested. Smart cat. The owners fixed the urination problem by addressing the flea issue.

If you are experiencing a problem with your cat urinating outside the box, think outside the box. Sure, your cat might be experiencing behavioral issues, but oftentimes a simple investigation into the medical side can reveal the true cause, and ultimately, a successful solution.