cat litter

UTIs in Cats: Causes, Symptoms & Cure

UTIs (urinary tract infections) are as frustrating as they are common. So can cats catch them, and if so, how serious are they? Are they a risk to your cat’s life?

What are UTIs in cats, and what causes them? Cats experience the same kind of UTIs as we do. Bacteria gets into a small wound in the cat’s urinary tract—urethra, bladder and kidneys—and causes an infection. This infection causes swelling and blocks pee from passing. The bacteria in the wound can spread, and the bladder or kidneys rupture unless you treat the issue promptly. A vet will diagnose the problem with a urinalysis and/or with X-rays. They will prescribe antibiotics if there is an infection, and surgery to remove bladder stones if these are the underlying cause.

The guide below first describes what causes UTIs and why they’re so serious. It will then detail the precise symptoms of UTIs in cats and how they’re corrected.

What Causes UTIs in Cats?

Urinary tract infections stop your cat from peeing as easily as it would want to.

A feline urinary tract infection is the same as the kind seen in humans. They occur when any part of the urinary tract—the urethra, the bladder, the kidneys, or the tubes between them—becomes infected with bacteria. The infection typically starts at the urethra and travels upwards, but in the event of kidney stones, the infection may begin further up.

For infection to occur, a wound must be present. That’s because the bacteria need an entry point. This wound could be a scratch, a graze or a puncture wound.

UTIs are a part of a network of related health conditions that can affect cats. FLUTD, or feline lower urinary tract disease, is a generic term that refers to a range of problems that affect your cat’s bladder and urethra. Bladder crystals and bladder stones fall under this banner, as does FIC (feline idiopathic cystitis) which is a lower urinary tract disease with symptoms but no obvious cause. This guide refers specifically to UTIs, but the symptoms and guidance are the same no matter the issue.

What Is a Feline UTI?

When bacteria find a wound, the UTI begins in earnest. The bacteria enter the wound and begin reproducing. Your cat’s body recognizes the intruders and begins the immune response, the purpose of which is to kill the bacteria.

Unfortunately, it’s this immune response that makes UTIs so painful and difficult. White blood cells spot the bacteria and send a message to the body that it has to get rid of them. While the white blood cells attack the bacteria, they also call for histamine to be sent to the area. Histamine is a hormone which promotes inflammation, widening the capillaries (tiny blood vessels) and making them more permeable for white blood cells. More white blood cells in the area of infection means more chance of fighting the infection off.

This swelling is the key cause of UTI symptoms. That’s because the tubes that link up the urinary system are narrow, so any swelling in their walls leads to them becoming blocked. With a blockage in place, urine cannot pass. This problem is made worse if the UTI occurs alongside a kidney stone or a bladder stone, as it then stands even less chance of passing.

While these symptoms endanger the life of the cat, the immune system doesn’t have a choice. If it allowed the bacteria to thrive then it would kill the surrounding tissue and keep spreading. This would kill the cat. The bladder or kidneys could also rupture which would kill your cat too. UTIs can be fatal, but not as fatal as sepsis, which is where infection reaches the bloodstream and attacks the internal organs.

How Do Cats Catch UTIs?

Cats catch UTIs from bacteria in their environment. The bacteria travel up the urethra to find the wound and thereby begin the infection.

Cats commonly catch UTIs from E-coli bacteria in their feces. If they don’t clean properly, it’s possible for the E-coli from your cat’s behind to get into its urethra and cause an infection. This can happen when your cat cleans itself, if your cat sits in something, if your cat’s litter tray is very dirty, or if your cat can’t clean itself properly.

UTIs are not catching, meaning that one cat won’t catch a UTI from another. That’s despite the fact that two cats can have UTIs at the same time. Rather than UTIs being transmissible, this occurs because the two cats are in the same environment and may experience the same issues (e.g. UTI secondary to kidney stones).

Are Some Cats More Vulnerable to UTIs?

Older cats are more vulnerable to UTIs than younger ones. That’s because older cats’ immune systems are weaker. There is therefore more chance of the UTI becoming serious and even killing an older cat, whereas younger cats typically recover well. Older female cats develop UTIs more often than males.

Cats that have other underlying health conditions are also highly susceptible to UTIs. Those with kidney stones and bladder stones will develop UTIs frequently, because the stones cause puncture wounds and grazes that bacteria can enter through. UTIs are also common for cats with diabetes mellitus.

That being said, key to recovery in either older or younger cats is prompt treatment. Antibiotics can quickly get rid of an infection, thus relieving the pressure on your cat’s bladder and allowing it to go to the toilet again.

What Are The Symptoms of UTIs in Cats?

There are many obvious symptoms of UTIs in cats. The problem is that these are shared with other conditions such as kidney stones. You therefore can’t rely on your gut instinct to tell you what’s wrong, and will need to take your cat to the vet both for diagnosis and for treatment.

Key Symptoms

Since urinary tract infections affect the urinary tract, it stands to reason that most of their symptoms would be related to urination. There are several things you may notice with regards to your cat’s toilet habits:

  • Straining to urinate, or being unable to urinate at all. The swelling in your cat’s urinary system blocks urine from passing. Your cat will push and strain to increase the pressure in its bladder in an effort to squeeze its pee past the blockage. If the swelling is big enough, nothing can pass.
  • Frequent attempts to urinate. Your cat’s bladder will be full because it can’t pee. It will therefore still feel the need to pee, and will try frequently to do so.
  • Blood in the urine. The wound that the bacteria entered may be bleeding. Further straining can cause the wound to open further. If there is a kidney stone present, it can cause other wounds which will become infected in their turn.
  • Urinating outside of the litter box. Your cat’s toilet behavior will change. It may start peeing in unusual places like in the bath or the sink, or in the corner of the room.
  • Damp patches around the genitals. These can occur because a small amount of urine dribbles out of the genitals. The high level of pressure in the bladder is enough to force out small amounts, but it remains hard for your cat to pee. Your cat may also groom the area frequently, another cause of damp patches. This may make your cat smell like pee.
  • Painful urination and irritability. UTIs are painful, and even more painful if kidney stones are present. Your cat may express its pain by yowling. It may also reject your affection because it’s irritable, a result of its pain.

Your cat may also display generic signs of being in very poor health. Lethargy is a common sign towards end-of-life. Lethargy is where your cat seems unmotivated to do anything—it doesn’t want to get up and walk around, doesn’t have the energy to eat, play or interact with you, and generally seems down in the dumps. In particular you should look for a change in behavior, so if your cat is normally very inactive, then this may not be lethargy; but if your cat is typically highly active, and is suddenly inactive, then you have a problem.

How Do You Cure UTIs in Cats?

skinny cat
If in doubt, see a vet. Your cat will eventually forgive you. Image courtesy of Wikimedia.

If your cat has a UTI, or any kind of lower urinary tract issue, you should look to get it treated as soon as possible. If the infection is allowed to spread, it could reach your cat’s bloodstream and cause sepsis. That’s where bacteria get into your cat’s internal organs and stop them from working. There are also complications that can arise from your cat not being able to empty its bladder. And besides all that, your cat is in a lot of pain and distress.

As such, you have to take your cat to the vet. The vet can identify what’s wrong with your cat and suggest an appropriate response.

How Are UTIs Diagnosed in Cats?

Urinary tract infections are diagnosed by urinalysis. While the symptoms above can suggest an infection, a urinalysis can confirm one. A urinalysis is a basic test where the vet takes a small sample of urine from your cat. They then analyze the urine in several different ways. Your cat’s health issue is clearly related to its urinary system, but this test will tell the vet what part of that system has gone wrong. They will look for:

  • Urine-specific gravity. The ‘gravity’ of the urine refers to how concentrated it is compared to water.
  • pH. A high pH of between 8.5 and 9.0 can indicate certain kinds of infectious bacteria.
  • ketones
  • glucose
  • bilirubin
  • blood
  • protein

The vet may also send the sample to a lab for what’s called a culture and sensitivity test. This is where the urine is further analyzed to identify the precise kind of bacteria infecting your cat’s urinary system. The reason for this is that antibiotics don’t work on all kinds of bacteria; different antibiotics specialize in killing different kinds of infection. So, to ensure the recovery of your cat, it may be necessary to identify the bacteria before treatment. Alternatively, the vet may offer you the kind of antibiotics that typically work for UTIs.


The vet may order an X-ray of your cat’s bladder and urethra. The point of an X-ray is to identify the underlying cause of the UTI. If it a bladder stone, it will show up. The vet may administer a contrast dye, which is a special non-poisonous dye which helps things show up better on X-rays.

The vet may also order an ultrasound to be done. An ultrasound is similar to an X-ray in that it allows the vet to see inside the body, but it’s done without radiation.

If the vet spots a bladder stone, then it is normally removed through surgery. If the stone isn’t removed then infection will almost certainly recur.


Urinary infections are caused by bacteria. Antibiotics kill bacteria and thereby cure the condition.

As stated above, there are many kinds of antibiotics available. Some are general purpose ones that work on most kinds of bacteria, while others work on more specific kinds. There are three ways that antibiotics stop bacteria:

  • Breaking down the outer coating of the bacterial cell, killing it
  • Stopping the bacteria from reproducing, allowing the immune system to kill all that remain, reducing the population
  • Stopping the bacteria from producing proteins vital to their survival

There are several ways that antibiotics can be administered. The initial dose can either be given by you or by the vet. But since you will have to continue treatment over an extended period of time, you will have to carry on with the course at home. Liquid antibiotics can be administered by mouth; there are also antibiotic pills that can be swallowed. There are certain antibiotic injections that can be performed by the vet, and which last for several weeks.

Another Urinalysis

After your cat’s course of antibiotics, it’s vital that the vet gives your cat another urinalysis. The point is to identify that the infection has been fully dealt with. If it hasn’t, then it could come back, and your cat’s problem would start all over again.

How to Prevent UTIs in Cats

It’s impossible to entirely prevent UTIs in your cat. However, there are small changes you can make that decrease the chances of another one affecting your cat.

  • Keep your cat’s litter box clean. The most common bacteria that causes UTIs is E-coli, and E-coli comes from feces. If you don’t regularly clean your cat’s litter tray then it could encounter E-coli bacteria every day.
  • Dietary changes. Poor diet can be the root cause of bladder and kidney stones. The more water in your cat’s system, the less chance of these forming, and the better its urinary health generally. A diet solely of kibble means your cat can’t easily get enough water, so feed your cat wet food.
  • Helping your cat clean itself. If your cat can’t groom itself as well as it used to, you could help by bathing it occasionally.

You should also take your cat to the vet occasionally for checkups. They can spot issues before they become too serious. Talk to your vet about how frequently to do this.