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Long-term diarrhoea in dogs and cats

Loose stools can become an ongoing problem in both dogs and cats. In medical terms, changes to the consistency of stools is termed chronic diarrhoea when it has been present for 2 weeks or more. This is quite common. In this article we look at the typical reasons and how to help your pet.

This article was written by a FirstVet vet


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Causes of chronic diarrhoea

There are intestinal causes of diarrhoea, which include problems with the small intestine, large intestine, problems with digestion and dietary issues. However, there can also be other causes that can have a secondary effect on the intestines, such as problems with the liver or pancreas.

Some common causes are:

  • Irritable Bowel Disease/Disorder (IBD)

  • Protein Losing Enteropathy (PLE) - a form of inflammation

  • Infections

  • Parasites (such as intestinal worms, Giardia, coccidia)

  • Cancer

  • Dietary intolerance or allergies

  • Drugs and medications

Signs of chronic diarrhoea

The symptoms will be dependent on the cause of the softer stools and may include:

  • Weight loss

  • Vomiting

  • Increased frequency of passing stools

  • Increased gas

  • Spots of blood

  • Mucus/clear jelly

  • Pain when passing stools

  • Straining

  • Change in volume of stools

  • Change in colour of stools

Treatment of chronic diarrhoea

Once a likely diagnosis has been made, treatment can be started. This may include a change in diet, wormers and faecal samples being collected and sent to the laboratory for testing. In more severe cases, an abdominal ultrasound or x-ray may be needed and there are also times when antibiotics are required.

Prevention of chronic diarrhoea

A good quality, balanced diet is essential. Always introduce any diet changes slowly and try to avoid scavenging. It is important to keep your pet up to date with regular worming treatment. It is also a good idea to check the garden regularly for any material or plants that may cause diarrhoea.

When to see a vet?

If you notice that your pet has diarrhoea, please get in touch with your vet. This is particularly important if you notice blood present, if your pet is passing large volumes of diarrhoea or has other symptoms such as weight loss, vomiting, pain or a reduced appetite.

Further information

Inflammatory bowel disease in dogs

Common infectious causes of diarrhoea in dogs and puppies

Food allergies in dogs and cats and how to manage them

Colitis in dogs - A common cause of diarrhoea

Still worried?

If you would like more advice on nutrition or raw feeding, please book an online video appointment to have a chat with one of our FirstVet nutrition vets.

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