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Why Does Cat Poop Smell So Bad? [And The Things You Can Do]

Bad smelling poop is not what any cat owner had in mind when they brought their cute kitten home. But it can and does often become an issue; at least for certain periods and at some point. But how and why do some cats experience this and what can you do about it? With these questions in mind, I decided to research and find out all that I could around the topic. I would like to share my findings here today to help you, as nobody wants to put up with foul smells for too long!

So, why does cat poop smell so bad? The most common cause of foul-smelling cat poop is in response to a poor-quality, or inappropriate diet. A sudden change in diet, even for the better, can also cause smelly feces. Bacterial infections, parasites, malabsorption disorders and anal gland infection are also other potential causes of odorous cat feces.

It’s worth pointing out that all feces smell, it does not matter if its your cat, another pet or any animal for that matter.

We of course cannot be entirely hypocritical here either. So, some smells can and should be expected somewhat.

However, the issue is when your cat’s feces smell so foul that you need to open all of your windows in your home, or you may even feel like you need to wear a mask.

If this comes about all of a sudden, it’s even more of a cause of concern.

Cat poop can reveal a lot about the condition of your cat’s health. While feces is not something most people want to think about, it is a crucial indicator of what’s happening and even going on inside your pet’s body (and more specifically, their digestive system).

The appearance, consistency, and smell of feces are essential factors to consider.

Generally, the stench of an unhealthy stool can linger in the air for far longer than any regular stool – and this is perhaps one of the most obvious examples that something is not quite right.

Taking the best care of your cat as you can, alongside making sure that they receive adequate and frequent veterinary care is essential.

It’s all part and parcel of supporting your cat’s health, and it is ultimately your responsibility as their guardian and owner.

Besides veterinary advice, you should make sure that your home is regularly and thoroughly cleaned.

You should disinfect the litter tray weekly and vacuum to remove cat hairs from your furniture and furnishings.

Let us now take a closer look at why cats’ poop can smell particularly foul.

We will then cover some of the most commonly asked questions, such as whether foul-smelling cat poop can be harmful to your health, and some of the best recommendations to proactively reduce and minimize the odor of your cat’s feces.

Or, be sure to keep reading to the end to get all the information you need!

Why Does My Cat Poop Stink So Bad?

Normal cat poop should be so mild that you hardly notice it. Equally, the occasional foul smell is not always a worry and does not always need further investigation.

However, foul-smelling poop can indicate that there is a problem if it persists and if it appears alongside other symptoms like a change in color or consistency.

Some owners will even detect a metallic smell coming directly the poop. This smell comes from digested blood that makes its way into the feces. So, this is one thing you may want to look out for.

More often than not, continued smelly bowel movements indicate more severe health problems which usually come from the stomach or intestines.

Issues within the stomach and intestines are usually caused by digestive disorders, parasites, and most commonly feeding an inappropriate or low-quality diet consistently.

So, one of the first areas to check is the diet. You may even find that most of the issues resolve with a change.

That being said, it’s always advised with anything health-related that you consult your vet.

They will be able to examine your cat and advise as to whether the smells could indicate that something more severe is going on.

In severe cases, it could be issues with the gastrointestinal tract, inflammation, infectious disease, or even cancer.

While it’s important to note them down here, this is not usually the case.

Instead, there are 7 main reasons cat feces tend to stink. Let us look at them in further detail:

Inappropriate Diet

Just as is the case with humans, we often know when we have eaten something that our bodies do not agree with when we end up going to the toilet. The same is the case with cats!

Cats are also sensitive to particular foods, that we may even not think could cause issues.

For example, some cats can react badly to foods that have a high vitamin content. Other cats do not do well on grains.

Sometimes, it can even be specific brands of foods that were even designed for cats!

This is why we should always do our best to seek out higher-quality options, as far as our budgets can stretch.

High-quality cat food will help provide a balance and abundance of nutrients that are all required for optimal gut health.

A high protein diet can also cause foul-smelling feces. While it is true that cats are carnivores and require a certain amount of protein; too much can be a problem too.

Cats can overdo it on the protein, especially if they begin to find and source their food outdoors.

You will soon notice a diet that is too rich in protein, and a simple diet change is often the solution to this problem.

In terms of a resolution, diet elimination is an excellent way to help identify what foods may be causing the digestive issues, resulting in foul feces.

Digestive Disorders

Perhaps the second most common cause of smelly feces are digestive disorders, and there are quite a few a cats can suffer from.

Problems with the digestive tract often develop over time and are the result of poor digestion and absorption of fats and starches.

Again, inappropriate foods are often the cause. However, these conditions can also develop in time as a cat age.


Cats have a naturally high prey drive, and will often seek out rodents like rats and mice.

They are very good at catching them too and are increasingly likely to consume them if your cat spends much of their time outdoors.

While normally this would not be a problem; the issue arises depending on what they catch and what their prey, in turn, is carrying.

If your cat becomes infected with Ecoli or Salmonella; this can cause inflammation, digestive discomfort, diarrhea, and ultimately smelly feces.


Parasitic infections can cause severe diarrhea and really upset your cat’s stomach resulting in very smelly feces.

They can be caught in a number of ways, but often are picked up from the environment by cats previously suffering from the condition.

Trichomonas and Coccidian are an example of just some parasites that can cause severe issues, and these particular parasites are most common in younger cats from multi-cat households.

Veterinarian interventions and antibiotics can help detect and treat the conditions caused by parasites and are the first port of call for any owner suspecting them.

Medication/Hormonal Changes

If your cat is suffering from a particular health condition or ailment, they may be placed on medications.

Some pain medications and those that specifically affect hormones tend to alter a cat’s natural chemical balance, which often results in foul-smelling poop.

If this is the case and you notice a change with recent medications, discussing this issue with your vet is advised.

They may be able to swap the medication for one that does not prove to be so problematic.

Anal Gland Infections

All mammals have anal glands that drain via gland ducts.

These ducts can become clogged, which necessitates manual draining.

Infection of these glands will make your cat produce a very runny and smelly discharge.

If your cat is suffering from an anal gland infection, you will know about it! Again, prompt treatment is advised to alleviate any pain and discomfort for your cat.

Is The Smell Of Cat Poop Harmful To Humans?

The smell of cat poop is not delightful to be around, but the odor alone is not harmful to your health.

Litter boxes can become a health hazard when they are not cleaned often enough; the build-up of urine and feces can result in harmful ammonia fumes. Ammonia is a toxic gas that can cause severe respiratory issues.

Ammonia can produce irritation of the lungs’ bronchial membranes, which can develop into a severe injury to the tissues in your lungs and trachea.

Symptoms often include minor headaches, feeling light-headed, and coughing.

Your cat is more likely to be affected, but nevertheless, you must regularly and sufficiently clean the litter box for the benefit of everyone!

One other potential health risk to be wary of with cat poop is toxoplasmosis (an infection caused by a parasite).

Humans can catch this from cat feces if the cat was to be carrying the parasite.

Pregnant women need to be especially careful, as toxoplasmosis can be especially harmful to them and their unborn babies.

For this reason, it is generally recommended that a pregnant woman does not change the litter box.

That being said, anyone cleaning a cat’s litter box, should take the appropriate measures and be wary of proper hygiene at all times.

Wearing gloves and thoroughly washing hands after each litter box change is a must. As is not touching any foods for some time after.

Toxoplasmosis is not common, but it is a condition to be aware of. Keeping a cat indoors and not feeding raw meat are approaches to minimize the chances of your cat getting this condition.

Equally, if you grow any food outside and have cats or neighbors with cats, you will need to thoroughly wash the foodstuffs before consuming them.

One other potential harmful parasite to be aware of is Tgondii.

Again this can be carried in cat feces.

This parasite can also infect individuals and can affect memory, including other cognitive functions.

Tgondii mostly affects people with compromised central nervous systems and the elderly, but anyone can catch it if unfortunate enough.

One final thing to consider is cat-scratch disease (CSD).

This is a bacterial infection found in cats that are carrying Bartonella henselae bacteria. If a human was to contract CSD by coming into contact with cat feces, they are likely to suffer from symptoms such as fatigue, swollen lymph nodes, headaches, body aches, low fevers, loss of appetite, and a sore throat.

As you can see, the smell of cat poop is not a danger – but what could be potentially being carried in it can be!

For anyone who changes the cat litter box, proper methods, appropriate hygiene, and other safety considerations should be prioritized.

How Can I Make My Cat’s Poop Less Smelly?

If you want to make your cats poop less smelly, then first and foremost you will want to try to identify the cause. You must ask yourself questions such as:

  • Has my cats diet changed recently?
  • Is my cat acting differently?
  • Are there any other signs or symptoms of ill health in my cat?
  • How long has the poop been smelling for?
  • Have there been any environmental or behavior changes in my cat?
  • And so on and so forth.

Since gastrointestinal tract, inflammatory disease, infection, and cancer can all be fatal and can be a cause of smelly stools; it is always advised to seek prompt veterinary care.

They will be able to examine and run some tests on your cat and recommend an appropriate course of action.

This is especially true if the foul smells have been going on for a while.

Nevertheless, there are some things that you can proactively do yourself to minimize the smell, improve your cat’s health and improve the home environment.

The following suggestions will help:

Disinfecting The Litter Box

Removing feces daily from the litter box is one of the best things you can do.

If your time does not allow this, aim to clean the litter box as often as you can. Many cat owners find it helpful to even create a cleaning schedule to keep on top of when it was last cleaned.

Be sure to use a scoop, wear gloves, and do all you can to protect yourself during the cleaning process.

Equally, sprinkling soda on the floor of the litter box helps to kill germs and eliminate foul odor.

Changing The Diet

Try to look for foods in the diet that your cat may not be responding well to.

Consider other brands and look at the ingredients on the packaging. You want one that has minimum additives, preservatives, grains, and other low-quality ingredients.

Try your cat on a new improved diet and routine, and if you do not know what to try, seek the advice of your vet.

Furthermore, digestive supplements can help lower the bacteria present in your cat’s body, and help them extract more nutrition from the food they are eating.

Grooming Your Cat

Sometimes we mistake smells coming from the litter tray with the cat itself! They may have even rolled in or have something smelly on them.

It’s a good idea to safely and appropriately wash your cat with a shampoo designed for cats. Use a comb to softly eliminate dirt, dead skin, and loose hairs too.

Cleaning Your Home

Again, cleaning your home and ensuring it is well ventilated can do a good job of reducing odors and improving the environment for you and your cat.

You should vacuum your carpets, couches, draperies, and chairs as often as you can. This should include spaces your cat frequents.

Vacuuming helps to remove dirt, dander, and loose hairs and will help your home smell fresher.

You can use air purifiers and furnace filters to keep the smell of your cat’s feces out of the house too.

Other tactics involve preventing or keeping your cat from accessing certain areas, moving their litter box to another room, or somewhere further away.

Consider A Waste Disposal System

There are many products on the market that have been designed to help eliminate pet poop odors throughout the home.

Perhaps the best for cats is the litter genie which you can get for a great price on Amazon.

It essentially enables you to collect feces and does an amazing job of locking in and removing odors. Take a look at some of the customer reviews on Amazon and you will see for yourself why they come so recommended!

Litter Genie Plus Pail (Silver) | Cat Litter Box Waste Disposal System for Odor Control | Includes 1 Square Refill Bag
  • REDUCE LITTER BOX ODOR: The makers of Diaper Genie present the Litter Genie Plus Pail to keep litter box odor in check! The pail holds up to 14 days of soiled litter per one cat, eliminating daily trips to the trash.
  • NO MORE STINK: The Plus Pail features a built-in antimicrobial to inhibit bacteria growth while the included refill bag features a multi-layer film to seal in odor and lasts 2 weeks longer than the standard pail refill.
  • USE IN 3 SIMPLE STEPS: Scoop clumps from the litter box and drop in the pail. Pull the handle to help seal in waste and odor!
  • A PURRFECT FIT: The pail's compact design is great for bathroom, under the kitchen sink, and home office spaces. The pail minimizes your trips to the trash!
  • PET PARENT MUST HAVE: Litter Genie Pails and Refills are necessities for any cat, small dog or rabbit parent! Trust the Litter Genie brand for a fresher smelling home.


A healthy, well-taken cared-for cat should not have any overtly smell foul-smelling stools.

While all feces does smell to some extent, if it is particularly offensive, has suddenly changed, becomes a regular occurrence or if it is accompanied by other issues then you are going to need to investigate further.

The appearance, consistency, and smell can reveal much about your cat’s health; smelly feces is an issue that must never go ignored.

Most foul-smelling poo indicates a problem with the gastrointestinal tract, infection, irritation, and in the worst-case scenario – cancer.

But before you panic and worry, the first step should always be to seek veterinary assistance.

They will be able to examine your cat and provide you with an appropriate course of action.

This may involve treatment, or it may be something more subtle like advising you to change the diet.

In the meantime, it’s essential to take care of the day-to-day chores such as removing poop, changing litter, vacuuming, keeping your home clean and smelling fresh, and grooming your cat when necessary.

If you find out that the issue is coming from the diet, you will also need to remedy this.

It may be with a change of specific food items or it may be a change of brands.

Two such areas to potentially look into are proteins and grains.

While cats are omnivorous and do require a certain amount of protein in the diet; too much can easily result in foul-smelling feces. More is not better.

Ultimately, it’s essential to understand what healthy cat poop looks like and what it should look like.

This way you can get a better insight into the condition of your cat’s health.

The ideal shape for cat feces is compact, small, and oblong; the amount and length should match the size of your cat.

The color should be dark brown, and it should be firm but not hard, as this could indicate constipation, perhaps due to a blockage.

While the smell of feces alone is not harmful to humans, cat poop can be hazardous – especially if the cat is carrying bacteria or a parasite.

To anyone in charge of cleaning the litter box and dealing with their cat poop, contact should be avoided at all costs. Ensuring gloves are worn and using proper handwashing practices are in many ways, essential.

How Often Should You Replace Cat Litter?

It is generally advised and recommended to replace cat litter at least twice a week. However, cat litter may require changing more regularly depending on specific circumstances, such as if your cat is suffering from diarrhea or illness. In this instance, daily or every other day is advised. How long cat litter typically lasts will also depend on the product used, your cat’s toilet patterns, along with other factors like where the litter box is kept, how many cats you have using the box, and the age of your cats.