Digestive disorders are not uncommon in animals because their gastrointestinal tract can be sensitive to various causes. If your cat or kitten has diarrhoea, it may be a simple stomach upset that will go away on its own. On the other hand, it can also be an indication of a serious illness. Therefore, you should keep a close eye on your cat if you notice that he/she is suffering from diarrhoea. In our guide, you can find out what can cause diarrhoea in cats, when you should see a vet about it, and what preventive measures you can take.

Essentially, there are many different triggers for disorders of the gastrointestinal tract in cats. Besides physical illnesses, psychological problems such as stress can also cause diarrhoea in your cat.

Possible concrete causes include:

Spoiled food
Food containing milk, sugar or starch (e.g. cakes, sweets, bread)
Eating mice or other animals
Feed allergy
Changing feed too quickly
Ingested foreign bodies
Worms and other parasites
Giardia (ciliates that infest the upper small or large intestine)
Viruses & bacteria
Poisoning from cleaning products, poison or poisonous plants
Various diseases of the stomach or intestines (e.g. pancreatitis, small intestine infection)
Hyperthyroidism
Stress and other psychological factors
Side effects of medicines such as antibiotics

If your cat has diarrhoea, it is not necessarily due to a serious illness. Ultimately, it is also a cleansing method used by the body in an attempt to eliminate foreign substances - similar to vomiting.

If the diarrhoea disappears by itself after a few days, a visit to the vet is not necessary. This is especially true if your four-legged friend is fit and is not behaving differently than normal. Observe your cat and their behaviour particularly closely during this time. This way you can assess exactly how your cat is doing and whether the diarrhoea will go away on its own.

Good to know!

If the diarrhoea is accompanied by a progressive loss of weight, you should have this checked by a veterinarian. This can be harmful or even life-threatening for the cat. In addition, the weight loss may be caused by an illness for which your cat's diarrhoea is only another symptom.

What are the typical symptoms?

Firstly, if your cat's faeces are not always the same in texture this is completely harmless. Now and then, a softer stool is completely normal and should not cause you any concern. Diarrhoea only occurs when the faeces are extremely soft or thin. If the smell of the faeces changes or is particularly strong, or if the colour of the faeces seems unhealthy, you should keep a closer eye on your cat. The colour and consistency can vary greatly during diarrhoea, but often provide clues to possible causes. Therefore, it is important to ask yourself some questions in order to get a quicker diagnosis from a veterinarian later on.

These questions are important and infer possible causes

What colour is the cat's faeces: light, dark brown reddish or black?
What is the consistency of the faeces: watery, mushy or slimy?
Are there worms or blood in the stool?
Does your cat have a fever? (If the temperature exceeds 39.5°C, go to the vet immediately!)

These questions can help you later to find the cause!

To identify whether you need to seek medical treatment for your cat's diarrhoea, you should look out for other associated symptoms. These can include:

Change in behaviour
Fever
Fatigue
Problems holding faeces and urine long enough
Loss of appetite, cat no longer eats
Cat no longer drinks

When is it time to go to the vet?

If you observe that your cat is suffering from diarrhoea and notice one of the previously mentioned changes in the faeces, you should now pay attention to whether additional symptoms occur. If the loss of weight continues, you should visit the vet with your cat. This is because a persistent loss of weight is harmful for cats and can even be life-threatening without countermeasures. If the weight loss is accompanied by diarrhoea, the latter may be a symptom of another disease. Therefore, seek advice from your veterinarian in case of persistent weight loss associated with diarrhoea.

Another danger is dehydration, which can also occur if a cat suffers from vomiting and diarrhoea at the same time. You can recognise this by pulling a fold of skin with two fingers and letting it go again. If the skin fold does not spring back immediately, there is a high risk of dehydration. In this case, too, it is absolutely necessary that you visit a veterinarian with your cat.

If your baby cat has diarrhoea, you should go to the vet immediately. This is because severe fluid loss coupled with diarrhoea is even more serious in kittens than in an adult cat. This also applies if your four-legged friend is pregnant or older, or suffers from a chronic illness. In all these cases, the body is more susceptible, so fluid loss should be prevented at all costs.

You should therefore also have the cause of your cat's diarrhoea clarified in any case. Potential dehydration can usually be recognised by very thin, water-like faeces. If your cat also seems apathetic, very lethargic or displays other abnormal behaviour, you should take it to the vet. You should also do this if your cat refuses to eat or drink and has a fever.

Your cat has diarrhoea – what can you do?

If your cat has acute diarrhoea, you should temporarily deprive him/her of food. However, this should last no longer than 10 hours, otherwise your cat may develop a fatty liver. Temporarily depriving your cat of food will help to normalise the imbalance in the digestive system. During this time, you should not let your four-legged friend outside, to ensure that they do not eat anything.
Provide your four-legged friend with fresh water and check whether he/she is drinking enough. This will help prevent dehydration. It may be advisable to add electrolytes to the water to compensate for the loss of minerals. It is best to discuss this with your vet.
If your cat's diarrhoea was only acute and completely disappeared after a short time, you can help with home remedies. After the fasting day, feed a light diet to slowly get the stomach and intestines used to food again. Easy-to-digest foods such as boiled boneless chicken with rice and carrots are recommended. In order not to overload the stomach and intestines, you should start with small amounts of food and then slowly increase the amount of food.
It is always advisable to take a faecal sample with you when you visit the vet. This way, the veterinarian can quickly rule out certain causes and also carry out an analysis to see if a poison is the trigger for your cat's diarrhoea. In this way, a suitable treatment can be initiated more quickly and with a greater chance of success.
If a food intolerance is responsible for your cat having diarrhoea, an appropriate diet can solve the problem. It is important that you know which foods your cat cannot tolerate. A test at the vet or a so-called exclusion diet can provide information about this. This way you can choose a suitable hypoallergenic cat food that is free of these ingredients.
If the cause of the indigestion is a worm infestation, the veterinarian will prescribe a worming treatment. This, in turn, may cause your cat to have diarrhoea due to the strength of the worms. As a rule, however, this should only be of short duration, because it serves to get rid of the worms as quickly as possible.

Tip!

To help determine the cause of the diarrhoea, you should consider whether something abnormal has occurred. This could be, for example, an abrupt change in food, medication or a change in your cat's behaviour.

Preventing diarrhoea in your cat

Due to the many causes that can trigger diarrhoea in cats, it is not easy to prevent this disease in its entirety. However, there are some rules you can follow to help your cat avoid certain triggers:

Feed your cat a species-appropriate diet
Do not give your cat human food
Keep toxic substances such as cleaning products in locked places or places that are inaccessible to your cat.
Do not plant plants in your garden that are poisonous to cats
Always keep foreign objects that could be swallowed out of the way.
Carry out vaccination prophylaxis as well as worming treatments

Conclusion

To prevent further health problems triggered by your cat's diarrhoea and to understand when you need to visit the vet, it is crucial that you know your cat well and always observe it closely. Behavioural changes should be a warning sign for you - especially if your four-legged friend is an outdoor cat. On the one hand, this is due to the fact that your cat will often defecate outside and you will not be aware if he/she has diarrhoea. On the other hand, the danger that your cat will eat something unsuitable is much greater than with a house cat. In any case, always be more attentive than usual if you notice that your cat is behaving unusually. This way you can react in time in the case of an emergency and take good care of your four-legged friend.

Author of the advisor

I am a journalist specialising in business, but I also write a lot about animals. For about 20 years I have had a second job as an animal psychologist with my own practice. I have worked as a lecturer at a school for health professions, where I designed and supervised the course in Animal Psychology of Cats. Since the topic of further education is particularly close to my heart, I hold seminars for pet owners and animal welfare organisations and have published four books on the subject of cat behaviour. Five meowing family members actively help with my research and writing.