Caring for Pets with Chronic Diarrhoea

By Dr Joanna De Klerk

Diarrhoea isn’t pleasant for you or your pet. It can be smelly, it can be messy, and at times, it can make your furbaby feel really unwell. 

Diarrhoea is when the frequency, consistency and/or the volume of your pet’s stools change. It can be acute or chronic. In this article, we’re going to focus on caring for pets with chronic diarrhoea, which is defined as diarrhoea that has been going on for more than three weeks.

The Digestive Tract

The digestive tract is the part of the body which breaks down, digests and absorbs the nutrients and fluid from food. The body then uses the nutrients for energy and biological processes. The digestive tract comprises of the stomach, liver, pancreas, small intestine and large intestine.

Problems with the digestive tract can lead to your pet having diarrhoea, sometimes with other symptoms too. It’s important to remember that diarrhoea is simply a symptom and not a disease in itself. Therefore, it’s important to work with your vet to achieve a specific diagnosis. This will help your furbaby receive the correct treatment.

What’s the Difference Between Small and Large Intestinal Diarrhoea?

Diarrhoea primarily originates from the small or large intestine, although it may originate from both. Sometimes it can be tricky to determine which one it is, but it’s important to work with your vet to figure it out, because you will have more success caring for your pet if you know the root cause.

These are the most common differences between small and large intestinal chronic diarrhoea:

Small Intestine Symptoms

  • Losing weight
  • Large volumes of faeces
  • Occasional vomiting
  • Gassy intestines
  • Sometimes black or tarry stools
  • Increased appetite

Large Intestine Symptoms

  • Small volumes of faeces
  • Increased frequency of defaecation
  • Sometimes fresh blood
  • Mucus in the stools
  • The need to defaecate even if there is nothing pass (many people mistake this straining for constipation)
  • Gassy intestines

Both small and large intestinal diarrhoea can cause dehydration, as fluid, electrolytes and nutrients are lost. This, among other symptoms, can lead to serious complications if left untreated.

Causes of Chronic Diarrhoea

There are multiple causes of chronic diarrhoea, categorised into small and large intestinal diseases. Your vet will need to determine which your pet has, as each individual diagnosis requires a specific treatment. However, you can care for your four-legged friend at home more easily if you know which category your pet’s diagnosis falls into.

Small Intestinal Diseases

  • Inflammatory bowel disease (IBD)
  • Infections (viral, bacterial, or parasites)
  • Ulcers
  • Lymphangiectasia
  • Pancreatitis
  • Exocrine pancreatic insufficiency (EPI)
  • Liver disease
  • Dietary intolerance or allergies (including food sensitivities)
  • Cancer
  • Hyperthyroidism (cats)
  • Kidney disease

Large Intestinal Diseases

  • Inflammatory bowel disease (IBD)
  • Irritable bowel syndrome (IBS)
  • Infections (viral, bacterial, or parasites)
  • Cancer
  • Dietary intolerance or allergies (including food sensitivities)

Home care of chronic diarrhoea primarily falls down to getting the diet right. Your furry friend may, or may not appreciate this, depending on whether he is a fussy eater! But a change in food is really important. It’s very common for people to think that a bland diet of cooked chicken and rice will sort out diarrhoea. But when it comes to chronic diarrhoea, in particular, it is not sufficiently balanced with nutrients to sustain your pet long-term.

Therefore, you might want to consider looking into a veterinary prescription diet. In the UK, the three most common prescription brands are Hills, Royal Canin and Purina. Your vet will be able to advise you which brand and product will suit your pet best. 

Dietary Management of Small Intestinal Chronic Diarrhoea

A diet to combat small intestinal chronic diarrhoea should incorporate the following:

  • High energy: This is important to address weight loss associated with the lack of nutrient absorption into the bloodstream.
  • Highly digestible: The better the food is digested; the more nutrients are available for absorption into the bloodstream. This helps prevents worsened diarrhoea due to the presence of undigested food.
  • Small number of protein sources: The fewer the sources of proteins, the less exposure to ingredients which could cause an allergy or intolerance.
  • Balanced level of fibre: Fibre falls into two categories; soluble and insoluble. It helps regulate the motility of the intestine and slow the movement of food through the large intestine. This increases the absorption of nutrients. Soluble fibres also boost beneficial bacteria (microflora) in the intestines. However, too much fibre will decrease the digestibility of the diet, so there must be the right balance.
  • Low fat content: This is particularly important for IBD, lymphangiectasia and EPI. Fats which are not absorbed properly can exacerbate diarrhoea. Fat also slows down the transit of food through the stomach, so a low-fat diet is great if your furbaby is also feeling nauseous. 
  • Omega oils: These are natural anti-inflammatories and will help calm down the intestines if they are inflamed.
  • High palatability: If your pet is not feeling very well, it’s important that the food is tasty.

Dietary Management of Large Intestinal Chronic Diarrhoea

A diet to combat large intestinal chronic diarrhoea should incorporate the following:

  • Highly digestible: Undigested food in the large intestine can worsen diarrhoea and also upset the balance of the microflora.
  • Increased fibre: This slows down large intestinal motility. Like fibre requirements for small intestinal diarrhoea, it should be a mixture of both soluble and insoluble fibres.
  • Hypoallergenic: Since often large intestinal chronic diarrhoea is caused by IBD or dietary intolerances, a hypoallergenic diet will ensure the proteins in the diet do not contain antigens which could cause a reaction.

Veterinary Care of Pets with Chronic Diarrhoea

It’s really important that you involve your vet in the management of your furbaby if he has chronic diarrhoea. In addition to changing the diet, they might prescribe deworming treatment and antibiotics, which can be both therapeutic and diagnostic, to assess for an improvement after treatment.

Your vet might also prescribe probiotics for your pet. These are beneficial bacteria which help create a normal, healthy microflora environment in your four-legged friend’s intestines. They do this via competing with bad bacteria, creating a difficult environment for bad bacteria to grow, and enhancing your furbaby’s immune system. Probiotics are available in the form of powders or pastes. Pastes are usually combined with other ingredients such a kaolin and pectin, which improve the firmness of the stools and help soothe the lining of the guts.

Another consideration is whether your pet needs vitamin B12 (cobalamin) injections. Your vet can give these on a weekly basis, or as needed. Many pets with small intestinal chronic diarrhoea have a cobalamin deficiency due to the inability to absorb it into the bloodstream adequately. Therefore, injections will help it bypass the intestines.

Finally, if the diarrhoea is very severe, your furry friend might require hospitalisation for intravenous fluids, intestinal protectant medications and supplementary nutrition. 

Take Home Message

Chronic diarrhoea, as the name suggests, can go on for a long time. Sometimes it can be lifelong. However, once the root cause has been determined, and your vet has provided specific treatment, you can care for your pet with chronic diarrhoea at home with a diet change and loving nursing care when needed.

Caring for pets with Diarrhoea