Diarrhoea in Cats This article is verified by a vet

Maine Coon in litter box

Diarrhoea could be the cause if your cat is visiting its litter box regularly.

Diarrhoea is one of the most common problems that cat owners will encounter. But what can cause diarrhoea in cats and when should you start to worry? We have summarised the most important information in this article for you.

How dangerous is diarrhoea in cats?

Diarrhoea in cats is not rare and in most cases isn’t dangerous for them. However, there can be serious causes of diarrhoea in cats. Diarrhoea can be life-threatening, especially in young cats and seniors, but other other age groups too due to the loss of fluids and electrolyte imbalance.

Causes: How does diarrhoea come about in cats?

If diarrhoea originates in the gastrointestinal tract, it is divided into large and small intestine diarrhoea. Diseases of other organ systems or various environmental stimuli can lead to diarrhoea in cats.

The following triggers are most common for diarrhoea in cats:

Diet-related diarrhoea

Diarrhoea in cats is very common due to incorrect feeding, food intolerances and food allergies. In most cases, rotten food or very quick changes in food are involved.

Infectious causes

Infectious pathogens like bacteria, viruses or parasites often pay a big role in the onset of diarrhoea in cats. The most common infectious causes include:

  • Viruses: Panleukopenia (parvovirus), feline coronavirus (FcoV), feline leukaemia virus (FeLV), feline immunodeficiency virus (FIV)
  • Bacteria: Campylobacter, salmonella
  • Parasites (mostly worms): Roundworms and tapeworms, protozoa (Giardia, coccidia), Tritrichomonas foetus

Diarrhoea in cats due to intoxication

Toxins and the intake of certain medication (e.g. antibiotics) can lead to diarrhoea in cats. To avoid severe side effects, you should only administer medication following discussion with the vet or other experts.

Metabolic and tumourous causes

Certain underlying diseases like pancreatitis or thyroid diseases often lead to severe diarrhoea in cats. Tumours of the intestine or other organs (paraneoplastic syndrome) are frequent triggers.

Structural changes to the intestine

In some cases, severe blockages (constipation), for example due to foreign bodies or changes in position within the intestine (kinks or invaginations), cause diarrhoea in cats. In this case, affected cats generally show further clinical symptoms, including a rapidly deteriorating general condition or vomiting.

Inflammatory bowel disease, IBD

Just like humans and dogs, cats can suffer from IBD. This is an autoimmune disease often linked to several other symptoms like fatigue and lacklustre, unkempt fur.

Symptoms: Further signs of disease

Diarrhoea in cats either emerges suddenly (acute) or over a longer period (chronic). There are big differences between the associated symptoms.

Whilst a mild food intolerance usually runs its course with no further complaints, severe diarrhoea mostly shows additional clinical signs. These sometimes severely affect the cat’s general condition.

The following symptoms are particularly common:

  • Changed faeces texture: watery, runny to mushy
  • Problems/pain when defecating
  • General symptoms like feebleness, fatigue and fever
  • Blood or slime in the faeces
  • Massive water loss (dehydration): weak pulse, fast heartbeat to cardiac arrhythmia
  • Further gastrointestinal complaints: loss of appetite and emaciation, nausea and vomiting, abdominal pain
  • Muscle weakness due to loss of electrolytes

Diarrhoea in cats can therefore cause several other problems, so you should always take long-lasting or particularly severe diarrhoea seriously.

Cute and fluffy ginger cat
Diarrhoea can cause many other symptoms such as abdominal pain in cats.

Diagnosis: When should I consult the vet about diarrhoea?

You shouldn’t underestimate diarrhoea in cats. You should consult your vet if the symptoms last longer than 24 hours or there are additional symptoms, because a massive loss of fluid and electrolytes can soon prove life-threatening.

An extensive discussion with the vet (anamnesis) is incredibly important for targeted treatment. Important indications such as a rapid change of food, consuming potentially toxic substances or the duration of diarrhoea so far help make the correct diagnosis.

Following the anamnesis, the assessment of the sick cat’s general condition is important. For instance, unstable circulation has to be normalised before the vet takes further diagnostic measures.

Special examinations for diarrhoea in cats

If the cat’s circulation is stable, the vet can start the special examination. A blood test reveals, based on the concentration of different immune cells, a lot about the possible cause. For example, an increase in eosinophil granulocytes (eosinophilia) is a sign of a parasite infestation or an allergic reaction.

A parasitological, bacteriological and virological examination can be initiated by means of a faecal examination.

Imaging procedures like X-rays or ultrasound can be deployed. For instance, swallowed foreign bodies or other changes to organs become visible. If infectious causes such as intoxication are ruled out, a diet-related, chronic diarrhoea can be diagnosed with an elimination diet.

Treatment: What to do if my cat has diarrhoea?

With acute diarrhoea, you should feed your cat a light food for the time being. For instance, this may consist of steamed chicken and unseasoned rice. Split its food into several small portions that you can offer your cat throughout the day. This helps to relieve your cat’s gastrointestinal tract.

You should only use other home remedies following discussion with an expert. If diarrhoea doesn’t improve with the help of light food within 24 hours, you should definitely consult your vet.

Further diarrhoea treatment for cats can be divided into symptomatic and special treatment:

Symptomatic treatment:

  • Fluid therapy (infusions) with added sugar and potassium (the latter only in severe cases following a blood test)
  • Painkillers
  • Medication to combat nausea (antiemetics)
  • Artificial feeding through a tube or light food
  • Medication to protect the stomach

Special treatment (depending on the cause):

  • Food-related trigger: Providing easily digestible foods
  • Infections: antibiotics if necessary or a deworming agent
  • Intoxication: medication if necessary to combat vomiting
  • Positional changes: surgical intervention

Prognosis: What are the recovery chances with diarrhoea?

The prognosis of diarrhoea in cats depends significantly on the cause and treatment. Diet-related diarrhoea generally progresses with no further clinical symptoms and can usually be treated quickly. Acute intoxication or unfavourable positional changes in the intestine can prove fatal if treatment starts too late.

Prevention: How can diarrhoea be prevented in cats?

Unfortunately not all causes of diarrhoea in cats can be prevented. However, the following preventive measures can minimise the risk:

Franziska G., Veterinarian
Profilbild von Tierärztin Franziska Gütgeman mit Hund

At the Justus-Liebig-University of Giessen I was extensively trained as a veterinarian and was able to gain experience in various fields such as small animal, large animal and exotic animal medicine as well as pharmacology, pathology and food hygiene. Since then, I have been working not only as a veterinary author, but also on my scientifically driven dissertation. My goal is to better protect animals from pathogenic bacterial organisms in the future. Besides my veterinary knowledge, I also share my own experiences as a happy dog owner and can thus understand and enlighten fears and problems as well as other important questions about animal health.

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