Get

In Your Inbox

Catster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Why Does Cat Pee Smell So Bad? 6 Vet Reviewed Reasons & Recommendations

woman covering nose while cleaning the litter box

If you own a cat, you’re intimately aware of how much their urine can smell. Dealing with a stinky litter box day in and day out isn’t exactly the best part of taking care of a feline. What exactly makes their litter smell so bad?

Here, we go over what makes cat urine smell so strong. We also give you tips on the best ways to eliminate the odor.

divider cat paws oct 2024

Best Ways to Combat the Smell

It’s important that you remove cat urine with the right cleaning products. Do not, under any circumstances, use bleach or any kind of ammonia products. These can mimic cat urine odor and will continue to draw your cat to the same area to urinate. There are DIY methods that you can use to remove the scent, but your best bet is to purchase a good enzymatic cleaner. This kind of product breaks down the uric acid in the urine, which is what can lead to a stinky odor.

You can also look into using deodorizers or even air purifiers, which can help. But be careful about using scented products around your cat. Many essential oils are toxic to cats, so it’s best to avoid using them around your feline friend.

But while using products to hide the smell can help, that’s all you’re doing: masking the smell. It’s always best to stay on top of cleaning it first.

Combating tough cat litter smells is an ongoing battle for pet parents but luckily, there are products out there designed to help! Two products that significantly reduce odors are the Hepper Litter Additive and the Hepper Enzyme Spray.

Image Product Details
Best Enzyme Cleaner Hepper Advanced Bio-Enzyme Pet Stain & Odor Eliminator Spray Hepper Advanced Bio-Enzyme Pet Stain & Odor Eliminator Spray
  • Works on multiple surfaces
  • Gentle yet effective
  • Lifts stains & set-in odors
  • Best Litter Additive Advanced Bio-Enzyme Cat Litter Deodorizer Advanced Bio-Enzyme Cat Litter Deodorizer
  • Neutralizes odor within cat litter
  • Cat-safe
  • Unscented
  • At Catster, we’ve admired Hepper for many years and decided to take a controlling ownership interest so that we could benefit from the outstanding designs of this cool cat company!

    divider cat paws oct 2024

    The 6 Reasons Why Cat Pee Smells So Bad

    1. Ancestors

    To understand why cat urine is so particularly strong, you must first understand where cats came from. The ancestors of domestic cats lived in the desert, and their bodies were designed to absorb as much moisture as possible from their urine in order to maintain hydration.

    Since modern cats evolved from desert cats, their urine is still quite concentrated in response to that original desert environment. Concentrated urine equals smellier urine.

    cat-peeing-on-the-floor
    Image Credit: nanniezwawa, Shutterstock

    2. Bacteria

    Cat urine is made up primarily of uric acid, with bacteria thrown in for good measure. After a cat pees and it has been sitting for a while, the bacteria have time to do their work.

    Fresh cat pee isn’t quite as smelly as it is when the bacteria in it start to decompose, which is what gives it that intense ammonia odor.


    3. Mercaptans

    Mercaptans are the next stage in the decomposition of a cat’s urine. As the bacteria continue to decompose, they start to release mercaptans, which are also found in a skunk’s spray. So, the longer a cat’s urine sits around, the smellier it gets.

    Cat using pooping or urinate clean sand litter box
    Image Credit by: Zoran Photographer, Shutterstock

    4. Intact Male Cats

    Male cats that haven’t been neutered yet tend to have more pungent urine, particularly compared to female cats. This is due to the extra testosterone and certain steroids that they are carrying around. Add this to the fact that intact male cats will spray urine as a part of marking behavior, and you have a recipe for a stinky disaster!


    5. Senior Cats With Kidney Issues

    Older cats with kidney problems are more likely to have urine that smells worse than that of young cats. When the kidneys don’t work as efficiently as they should, it can contribute to more concentrated urine or cause higher bacteria levels. Both of these changes can create stronger-smelling urine.

    senior tabby cat lying on the ground
    Image Credit: ROBERT ENRIQUEZ, Shutterstock

    6. Just Sitting There

    The longer the urine sits, the stinkier it gets. So, if the litter box isn’t cleaned often enough, you can certainly expect to smell it. Also, cats sometimes pee outside of the litter box. This could be from a health or behavioral problem, but it could also be from them accidentally peeing over the side.

    If you’re unaware that this has occurred, the urine will go through the decomposition process, and the smell will guide you to where you need to clean.

    divider cat paws oct 2024

    Next Steps

    So, now that you know what causes the strong smell of cat urine, let’s go over the best ways to eliminate it.

    First, if you have an intact male, you should look into having him neutered. This will help eliminate the spraying and take the strong urine scent down a notch. It’s best to get this done while the cat is still young, as the older he is, the more likely that he’ll still occasionally spray.

    Second, if you have a senior cat, you should regularly visit your vet, particularly if your pet has kidney issues. The vet may suggest giving your cat extra fluids, a different kind of food, and prescribed medication that may help them live a longer and much more comfortable life. It should also help reduce the pungency of their urine odor.

    If you need to speak with a vet but can't get to one, head over to PangoVet. It's an online service where you can talk to a vet online and get the advice you need for your pet — all at an affordable price!

    PangoVet_Mention-in-Content for PangoVet2 save money

    Finally, you’ll need to stay on top of cleaning the litter box and anywhere else that your cat might be urinating. If you suspect they are peeing in places other than the litter box, you can invest in a blacklight and do a little sleuthing.

    man cleaning low entry cat litter box while cat watches
    Image Credit: New Africa, Shutterstock

    divider cat paws oct 2024

    Conclusion

    Now that you’re armed with knowledge and a few resources, you can fight that nasty cat urine odor. Keep the litter box clean, and try to find any accidents before they become the source of a stinky problem.

    If you’re concerned about your cat urinating outside of the litter box, speak to your vet. Several health problems can cause this behavior and would need to be checked out, just in case.

    Also, ensure that you’re using the right litter (cats prefer something with a more sand-like texture, and unscented is best) and that the litter box is in the best place. Your cat’s comfort has much to do with litter box behavior. A happy cat can sometimes mean a less stinky mess.


    Featured Image Credit: catinsyrup, Shutterstock

    Want content like this delivered to you?

    Sign Up For Our Newsletter

    News, insights, expert advice, and everything cat

    * By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.

    How useful was this post?

    Click on a star to rate (you can leave written feedback after clicking submit)

    Help us improve Catster for pet parents!

    Your feedback really matters.

    What did you like about this post? Also how can we improve it?

    Join the conversation

    2 Responses

      1. Hi Melissa, you might want to try an enzymatic spray: https://www.catster.com/lifestyle/best-enzyme-cleaner-for-cat-urine/. But we do recommend you share your concerns with a vet at www.pangovet.com, they can suggest some tips to manage the smell but, more importantly, help you figure out if your cat might need to go to a vet’s clinic for treatment.

    Leave a Reply

    You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.

    Talk With A Vet Online

    Peace of mind,
    anywhere, anytime

    Affordable vet advice

    Does My Cat Understand Smiles? The Facts & FAQ

    Most of us work hard to have a communicative relationship with our cats. We talk to them multiple times per day, as well...

    Can Cats Die from Tooth Resorption? Vet Reviewed Facts & FAQ

    Naturally, one of the first questions that come to mind when our pets are diagnosed with a health condition is “can my pet...

    Can Cats Eat Potato Chips? Vet-Verified Nutrition & Health Advice

    You settle down in front of the TV, open your bag of potato chips, and crunch your way through your favorite salty snack....

    250 Cat Names That Start With M for Beautiful & Intrepid Felines

    Coming up with a name for a new pet is sometimes easy, but usually, it can be quite challenging. Baby name lists are...

    More related

    How to Introduce Two Male Cats: 7 Approved Tips

    Introducing two cats to each other can be a real challenge. Cats are very particular animals that tend to warm up to new...

    Can Cats Eat Thyme? Vet-Reviewed Facts

    Cats are obligate carnivores, which means the vast majority of their dietary intake should come from meat and other animal-based ingredients. However, it...

    Can I Flush Cat Litter? Vet-Reviewed Facts & FAQ

    Dealing with your cat’s litter is probably one of the least pleasant elements of having a feline companion. If you live in an...

    How Much Will Cat Sitting Cost Me in 2025? Hourly & Daily Rates

    If you’re going out of town for a few days, you’ll need someone to look after your cat while you’re gone. A cat...

    Keep reading

    How Many Kittens Are in a Litter? Vet-Reviewed Health Facts

    Is there any baby cuter than a kitten? They are soft, adorable, tiny little lion-like creatures with the cutest mannerisms. Have you ever wondered how many kittens a cat could have when they reproduce? Or, maybe you suspect your kitty...

    cat breastfeed new born kitten

    When to Call an Emergency Vet & How to Find One for Your Cat – Vet-Approved Advice & Guidance

    Cats are great at masking pain, which makes it more difficult for kitty parents to identify what’s an emergency and what’s not, particularly early on. Here are some signs in cats that call for emergency vet care, no matter the...

    A cat with an emergency first aid kit.

    How Long Can You Leave Wet Cat Food Out? Vet-Verified Health & Safety Info

    The clock starts ticking as soon as you open your cat’s can of food. Feline wet food will grow bacteria, accumulate bacterial toxins, and spoil much faster than dry food. Generally, wet cat food can only stay out for around...

    cat eating wet tuna food

    Will CBD Help My Cat With Seizures & Epilepsy? What You Should Know (Vet-Reviewed)

    Like humans, cats can be affected by seizures and epilepsy. During a seizure, your cat’s body will convulse uncontrollably. This causes the body to twitch, tremor, or shake. When a cat has repeated seizures, they are typically considered to have...

    cbd oil

    Why Does My Cat Lick Plastic? Behavior Explained (Vet-Verified)

    Cat parents know that felines can do some very odd things at times. Whether suddenly running up the walls (literally) or fitting themselves into the smallest space they can find, cats engage in behaviors that seem to have no reasonable...

    cat with plastic bag in the kitchen

    Why Is My Cat Pooping Outside the Litter Box? 5 Vet-Reviewed Reasons & Tips to Stop It

    You’re getting so sick of it. You are providing what you think your cat needs for bathroom time—and it’s never been a problem before—but all of a sudden, you’re finding piles of poo randomly throughout the home. You’ve tried to...

    siamese cat sitting next to enclosed litter box

    Do Devon Rex Cats Shed a Lot? Tips to Reduce Cat Hair & FAQ

    The Devon Rex cat, with its pixie-like appearance and charming personality, is an increasingly popular breed of feline. While these cats are known for their curly hair, endearing nature, and playful antics, one of the most common questions prospective owners...

    woman brushing calico tortoiseshell Devon Rex

    Do I Need to Expose My Cat to Sunlight for Them To Stay Healthy?

    You’ve probably read more than a few stories about the importance of getting enough vitamin D, “the sunshine” vitamin. It plays a critical role in muscle and bone development, nervous system functions, and immune health for humans. But do domestic...

    American Polydactyl cat walking outside