Cat Has Diarrhea But Seems Fine: What to Do & When to Worry

When our cats show any signs of illness it is easy to overthink and panic. We want to make sure our cats have the happiest and healthiest lives possible, and cannot bear to think they’re not feeling their best!

One of the most common signs of illness in cats is diarrhea – our cats cannot tell us they are in pain, but seeing runny or loose excrement in their litter tray is hard to miss. But, what if your cat has diarrhea but seems fine? Should you panic that something is wrong? Or has your cat just eaten something different from usual that has mildly disagreed with them?

Your cat can have diarrhea for many reasons, including stress, a change in their diet, or toxic poisoning.

However, if your cat seems fine in all other ways and their diarrhea is a one-off incident, you don’t have much to worry about. Yet, it is key that you understand and notice your kitty’s litter box habits so that if there is something seriously wrong you can catch it fast.

In this article, I will run through the reasons why your cat could have diarrhea but no other symptoms, what to do, and when you need to contact your vet in case of a more serious issue.

Why Does My Cat Have Diarrhea?

To understand better when you need to be concerned that your cat has diarrhea, here are some of the most common possible causes. As a digestive issue, the majority either fall under food-related reasons or gut infections. However, there are also several more serious but less common reasons too which I will cover.

Bear in mind that this isn’t an exhaustive list – there are many reasons why your cat has diarrhea. However, these are the most common causes that vets have identified.

Food-Related Causes

The most common reason your cat has diarrhea is that they have eaten something unusual to them. This doesn’t necessarily mean something bad for them, just something different from what they are used to. Here are some examples of what I mean.

1. Change of Diet

Switching up your cat food to another brand which is made from new ingredients with different proportions of carbohydrates, proteins, and fats could be all it takes to give your cat looser stools. This is a common reason your cat has diarrhea but no other symptoms. They’re well and healthy, their digestive system is just adapting to the change in nutrients.

There are several reasons why you may be looking to change your cat’s diet. There may be a new brand of food you’d like to try, or perhaps you want to swap to a cheaper product. It may also be advised by your vet to change your feline’s food if they are overweight or have a special disease, such as kidney disease. Cats at different stages of life also need different nutrients, so you might be swapping to food more appropriate for their needs. 

When you do need to change your cat’s food, be sure to do it gradually so that it isn’t a shock to their digestive system. This should prevent any sickness and diarrhea. Besides, cats are creatures of habit, and changing their food suddenly can make them less likely to eat and get all the nutrients they need. In fact, if this is the reason your cat has diarrhea, you may also notice your cat not eating much but acting normal.

2. Spoiled Food

Another possibility is that the food your feed your cat has become spoiled. Check the expiry date on the packet – has it passed? If so, throw it away and buy a new bag. If not, give it a sniff and see if it smells like it has gone off. Even if the best-before date is in the future, the food could have gone off if it hasn’t been stored correctly.

Dry food can turn stale if you haven’t been storing their kibble correctly, especially in the warmer summer months. Wet food spoils even more easily than dry kibble. Once you open a can of wet food, it needs to be stored in the refrigerator to keep it fresh. Moreover, make sure you throw away any wet cat food in your cat’s bowl that it hasn’t eaten within the hour. Wet food left out longer than this can attract bacteria and germs which will make your cat sick.

Eating spoiled food can easily give your cat diarrhea, just as eating gone off meat would make us feel sick! Another giveaway sign is if your cat has stopped eating dry food but eats treats. If you think this could be the case, it’s no major cause for concern. Simply buy a fresh packet of food and your cat’s diarrhea should pass.

3. Eating a Foreign Object

Alternatively, your cat could have ingested a non-digestible material such as synthetic fabrics, wool, rubber, and paper. This is much more common than you think. Cats are curious creatures and can often find small objects lying around the home that they decide to put in their mouths. String and elastic from cat toys are also commonly ingested.

When cats accidentally ingest these foreign objects, they can rub again the lining of the GI tract and cause irritation. As a result, the absorptive function of the intestine is impaired, and it stops absorbing water as it should. This leads to runny, watery stools that lack any form of consistency.

In other cases, the foreign object can become lodged inside the intestine and cause an obstruction. While the blockage will prevent solid stools from being passed, watery liquid can fit around the outside. This can cause a paradoxical situation where your cat has diarrhea and constipation. The blockage needs to be removed so their bowel movements can return to normal.

4. Eating a Toxic Substance

There is also a chance that your cat has ingested a toxic substance. There are all kinds of toxic substances lurking in our homes. This includes many human foods such as onions, garlic, and chocolate. Painkillers, anti-freeze, and cleaning products are all also poisonous to our feline friends, as are many common houseplants. If you have an outdoor kitty, there are even more toxic substances lurking outside the home.

Diarrhea is one of the most common symptoms of toxicity in cats as many toxins interfere with normal digestion. Plus, diarrhea is the body’s way of trying to flush the toxin out as quickly as possible. The diarrhea might be mild or severe, depending on precisely how much and of what has been eaten.

If your cat has diarrhea but seems fine, I wouldn’t worry too much. The symptoms will likely subside once the foreign object or toxins have worked their way out of its system. However, make sure your cat doesn’t get dehydrated and speak to your vet if your cat’s condition deteriorates. If severe toxicity goes unchecked, it can lead to coma or death.

5. Food Allergies

It is possible that your cat has diarrhea or vomiting but is acting normal because of a food allergy. Your cat can develop allergies to food at any point in their lives, even to food that you have been feeding them since they were a kitten. However, most allergies would have developed by the time your cat is five years old.

Interestingly, it is usually the protein in cat food responsible for allergies. This comes as a surprise to many as cats are obligate carnivores and need meat and protein to survive. But it’s true – the most common food allergies in cats are to chicken, beef, and other protein sources. However, sensitivities to any food substances are possible.

If your cat has diarrhea but seems fine, food allergies are unlikely. This is because most cats with allergies typically also have itchy skin and other skin conditions such as rashes, alongside losing their hair due to overgrooming. If you don’t notice these other symptoms, you can generally rule food allergies out as their cause for diarrhea.

Gastro-Intestinal Infections

The second most common reason cats have diarrhea is because of an infection of the gut. In fact, most cats will develop a GI infection at some point in their lives. They can be caused by viruses, bacteria, fungi, and parasites. For the sake of this article, I have split all GI infections into two categories: gut infections and parasitic infections.

1. Gut Infections

Infections of the gut affect how your cat’s digestive system functions and will alter the absorption and digestion of food. When diarrhea is a symptom, this is usually because the infection causes the cells of the intestine wall to become inflamed. This impairs their ability to readily absorb water from the bowels as the fecal matter passed through, causing poop to be runny and watery.

There are a whole host of different GI infections, with some of the most common being viral infections such as rotavirus and panleukopenia. Both of these cause acute diarrhea which lasts for less than 2 weeks. Bacterial infections can also behind their stomach upset, particularly if your cat has bloody stool but is acting normal.

You’ll need to visit your vet to get an antiviral medication or course of antibiotics to treat any of these infections. Most treatments will last 1-2 weeks, after which your cat’s bowel movements should have returned to normal. If the treatment hasn’t worked and your cat is still suffering from diarrhea, go back to your vet. There is a possibility that the infection you’re dealing with is resistant to the medication prescribed.

More serious and long-term infections cause also cause diarrhea. These include feline immunodeficiency virus or leukemia. However, if your cat has one of these more serious and life-threatening diseases you will see other symptoms too, including lethargy, loss of appetite, and signs of dehydration.

2. Intestinal Parasitic Infections

Unlike typical infections caused by viruses, bacteria, or fungi, intestinal parasitic infections are caused by an organism that lives inside your cat and causes disease. Fleas are a common parasite, but these won’t cause stomach issues as they are external parasites. However, worms that live inside your cat’s body can cause sickness and diarrhea.

When talking about intestinal worms, roundworms and hookworms are the most common types. Roundworms are free-swimming worms that feed on nutrients your cat consumes. They can grow extremely long and affect the inability of the intestines to absorb water and nutrients. On the other hand, hookworms latch onto the cells of the intestine and feed on the blood. This leads to inflammation, poor absorption, and diarrhea.

If your cat has diarrhea but seems fine, the parasitic infection might only be mild. However, in most cases, you’ll spot other symptoms. Examples include an increase in appetite, weight loss, and a dull coat. You might also spot blood in the stools or small white specks that look like rice.

Young cats are more likely to get worms as they can be passed on by swallowing larvae from their mother’s milk. Plus, worms can also be inherited from their mother. If your kitten has diarrhea but acts normal this could be why. Older cats can also get worms though, from eating prey that has been infected with worms, having fleas and eating them when grooming themselves, or drinking contaminated water.

Stress & Anxiety

Just as stress can manifest as sickness and diarrhea in humans, the same is true for our felines. This is because the body responds to stress by releasing hormones and other chemicals. These interfere with the healthy gut microbiome and can cause short-term outbreaks of diarrhea. Therefore, if your cat has diarrhea but seems okay, it could be that they’re stressed.

However, in most cases, you’ll also notice other signs of stress in cats. Common symptoms include either a loss or gain of appetite, sleeping more than usual, poor and patchy coat, or weight loss/gain. There are also several behavioral symptoms of stress, such as an increase in aggressive behavior, excessive meowing, and stopping using their litter tray altogether.

If you think your cat is stressed, it is key you find the cause of the stress. Cats don’t respond well to change, and even the smallest alteration to their daily routine can make them anxious! Some common examples of situations that could lead to stress in cats include:

• Moving to a new home or neighborhood
• Welcoming a new baby to the family
• Adopting a new cat or another pet
• Having strange and unfamiliar guests in your home
• Changing your cat’s food or feeding schedule
• The loss of a pet or family member
• Loud noises such as fireworks or construction
• Moving the furniture around in your home
• Changes to your schedule and usual routine
• Neighborhood cats invading their territory
• Moving the litter box or changing the litter

Where possible, you should remove the stressor from your cat’s home environment. However, sometimes this isn’t doable. In these cases, ensuring your cat always has somewhere to hide and escape to or sticking to the same daily routine can make a huge difference to their lives. Whenever you do need to introduce a change, do so gradually. Your cat will respond to the change better and will be less likely to suffer from stress and diarrhea.

Medical Conditions & Illness

There is also a chance that your cat is experiencing diarrhea due to an underlying medical condition. The most common are hyperthyroidism, diabetes, irritable bowel disease, kidney disease, and liver disease. Each of these is serious and needs to be treated by a vet.

Having said that, don’t panic just yet! If your cat has diarrhea and seems fine, medical conditions are unlikely to be the cause. Most health issues have a range of clinical symptoms that you’ll notice alongside your cat’s unhealthy bowel movements. However, I wanted to mention them here so if you do notice any of the other symptoms you can get your cat to the vet as soon as possible.

1. Feline Hyperthyroidism

Hyperthyroidism is a common disease that typically affects older cats. Cats with this condition have an enlarged and overactive thyroid gland. This gland produces thyroid, a hormone responsible for regulating metabolism. When the thyroid gland is overactive, it produces excess levels of the hormone thyroid. This causes the metabolism to increase above normal levels.

An increased metabolism has all kinds of effects on the body. In regards to digestion, it causes the intestine to push the contents of the bowels through the body much more quickly. The intestines, therefore, have less time to absorb water from the fecal matter, so more liquid is passed with it. This is what causes diarrhea.

The signs of feline hyperthyroidism are very subtle at first and gradually become more apparent as the disease progresses. Diarrhea is a symptom and often one of the first noticed by their owners. So, even if your cat seems fine, it is worthwhile having hyperthyroidism ruled out. Other symptoms you might notice include weight loss despite an increased appetite, hyperactive or aggressive behavior, and weakness.

2. Irritable Bowel Disease

Irritable bowel disease (IBD) is another possible cause of diarrhea in cats. Sadly, there is not much known about the cause of the disease and so it can be difficult to treat. Most researchers agree that it is a result of genetic and environmental factors. However, it can sometimes be caused by things such as food allergies or bacterial infections.

Regardless of the cause, IBD is the result of chronic inflammation. If your cat is experiencing diarrhea as a symptom, it’s usually a sign that the inflammation is in the intestines. As the cells of the intestine become inflamed, they start to thicken. This makes it more difficult for them to absorb water and nutrients, causing your cat’s stools to become watery.

However, inflammation can happen anywhere along the GI tract. The stomach is another common site of inflammation. When these cells are inflamed, it leads to vomiting. It is also possible for a cat’s intestines and stomach to be infected, leading to both vomiting and diarrhea. Other clinical signs to watch out for include weight loss and poor appetite.

3. Diabetes

Diabetes is another common disorder in cats that is due to a hormone imbalance. This time, the hormone responsible is insulin which is involved in regulating blood sugar levels. Diabetic cats either don’t produce enough of this hormone, or their response to the hormone isn’t strong enough. This causes cats to be unable to control their blood sugar levels effectively.

As there is typically more sugar in their blood, water will be drawn out from cells and into their bloodstream. This can lead to diarrhea and increased urination. To deal with fluid loss, you may also notice your cat is thirsty all the time. They may also have an increased appetite as there is no way for them to extract the sugar they have eaten from their bloodstream, making them feel permanently hungry.

4. Liver Disease

Liver disease is relatively common in cats, which is where the function of the liver is impaired. This organ is usually responsible for processing waste and toxins, alongside breaking down fats and proteins, storing minerals and glycogen, and producing bile needed for digestion. As a result, liver disease can cause varying symptoms throughout the entire body.

Typically, the most common signs of liver disease are loss of appetite, weight loss, and increased lethargy. However, liver disease can also cause diarrhea and vomiting in felines in severe cases and depending on the cause. With that being said, if your cat has diarrhea but no other symptoms, liver disease is unlikely. Still, it is worth speaking to your vet to rule out this condition.

5. Kidney Disease

The kidneys also have a function in processing waste and toxins and maintaining the electrolyte balance in the body. As such, kidney failure can cause an electrolyte imbalance and lead to diarrhea in cats. However, as with liver failure, diarrhea is one of the later symptoms to present. At the onset of the disease, the most common signs are increased lethargy, loss of appetite, and increase thirst and urination.

It is important to pick up on these early signs as soon as possible. Kidney disease is life-threatening, and most cats diagnosed with the early stages of the disease only have an average survival time of three years. If the condition goes unchecked until the later stages, survival time drops to a few months. Hopefully, your cat doesn’t have kidney disease, but if in any doubt definitely book an appointment with the vet.

When Should I Worry About Diarrhea?

With so many potential causes for diarrhea in cats, it can be difficult to know when to worry. Should you panic if your cat has diarrhea but not other symptoms?

In most cases, if your cat has diarrhea but seems all right, you shouldn’t be too concerned. Most of the major and more serious issues are all accompanied by other symptoms. For example, diarrhea is unlikely to be the first symptoms you notice if your cat has kidney disease and liver disease. Similarly, more severe GI infections which could be life-threatening will present themselves in other ways, too.

However, if their diarrhea gets severe – even if it is still the only symptom – you should immediately speak to your vet. Severe diarrhea can lead to dehydration which can be extremely dangerous to your feline! So that you know what constitutes as “severe”, here are all the things you shouldn’t ignore:

• Consistent diarrhea that lasts over 24 hours
• Intermittent diarrhea that lasts over 2 weeks
• Bloody stools even if acting normal
• Pooping upwards of five times per day
• Stools that are green or yellow in color
• Diarrhea while taking other prescribed medication
• Other symptoms in combination with diarrhea
• A kitten or old cat with diarrhea
• Your cat is already battling another medical condition

If any of these are true for your feline, call your vet immediately to ask for advice. It may be nothing serious, but it is always better to be safe than sorry! They will be able to advise you on treatment and ensure your cat is back to their old selves in no time at all.

What Can I Give My Cat For Diarrhea?

If your cat has diarrhea, never try to medicate them at home.

You might have read that several over-the-counter drugs and human medications can improve symptoms. In reality, these could make your cat’s tummy troubles worse. You should always speak to your vet for treatment, rather than dealing with the issue yourself at home. They’ll be able to treat the underlying cause rather than the symptom, which is much more effective.

However, if your cat has runny stools but seems otherwise fine, it might not be worth a trip to the vet. So, you may be looking for some home remedies for cats with diarrhea. While there isn’t a specific treatment – you will have to wait for the diarrhea to pass – there are some things you can do to make your cat’s sickness a little easier to deal with.

1. Feed Them Regularly

If your cat has diarrhea, you may be inclined to withhold food from your cat. If they’re not eating, they can’t be pooping, right? Wrong! Your cat will already be losing nutrients through their runny stools, so it is important to keep feeding your cat. They’ll need all the strength they can to recover from whatever is causes them a stomach upset.

With that being said, you may need to change your usual feeding routine. If you only feed your cat twice per day, break their meal up into several smaller meals instead. This is much easier for their body to handle. Also, avoid giving them treats or any other rich or fatty food and stick to plain boiled chicken. You can gradually reintroduce your cat’s regular food and return to their usual feeding schedule over a few days as they start to feel better.

2. Provide Lots of Fresh Water

A lot of extra water will be lost if your cat has diarrhea, especially if your cat is pooping more frequently than usual. So, you need to ensure you provide plenty of fresh water for them to drink to replenish the amount lost. Dehydration is the biggest and most serious complication of diarrhea and motivating your cat to drink prevents this from happening.

Purchasing a cat water fountain could add some extra encouragement if needed. Most cats show a preference for running water and so will drink from a fountain more readily. Another option is to make their water more appealing by adding a little chicken broth or juice from a tin of tuna. You can also feed your cat wet food which has a higher water content when compared to kibble.

3. Let Them Rest

To recover quickly, your cat will also need plenty of rest. During sleep is when the body heals itself and has more time to focus on strengthening the immune system. Try to not encourage them to play until their stools have returned to normal and try not to wake them up if you see them sleeping.

However, be mindful of just how sleepy your cat seems. Whereas they will want to sleep a little more for their body to recover, increased lethargy should be a sign of a more serious illness. Indeed, it is a symptom of liver disease and kidney disease, the two most serious medical conditions on this list. If in doubt, speak to your vet for guidance and advice.

CONCLUSION

So, should you worry if your cat has diarrhea but seems fine? It depends on the situation! But, in most cases, if your cat has no other symptoms then there is no major cause for concern. If this is the case, it is best to care for your cat at home by giving them plenty of fresh water to drink, small and regular meals of plain boiled chicken to eat, and letting them get a lot of rest.

However, severe diarrhea can be a sign of a more serious illness. If it lasts consistently over 24 hours, intermittently over 2 weeks, or in combination with any other symptoms you should speak to your vet. If in doubt, you should always speak to your vet for advice, too – after all, it’s better to be safe than sorry!