Diarrhoea in Dogs

Diarrhoea in dogs is an extremely common problem that most dogs will suffer from during their lifetime.  Although it can be distressing for owners, most cases of diarrhoea will resolve on their own relatively quickly.  However, diarrhoea can be a symptom of a more serious condition that will need treatment, so it is important to recognise warning signs and know when to visit the vet. 


Signs and Symptoms

Diarrhoea is defined as the passage of frequent and loose stools. The stools are often malodorous and soft to liquid in composition.  The body forces food to rapidly transit out of the body to protect it from ingested toxins or harmful bacteria.  Diarrhoea may be accompanied by flatulence, abdominal discomfort, soreness around the rectal area, vomiting and weight loss.  Diarrhoea may be acute in which it starts rapidly and often resolves relatively quickly with conservative treatment or veterinary therapy.  Or it may be chronic in which the diarrhoea can last for several weeks and can be more complicated to find the cause and treat effectively.  It may also involve the small bowel, causing large volumes of watery diarrhoea or alternatively the large bowel, causing frequent straining to pass small volumes with sometimes jelly, mucous or blood coating the stools.



It’s important to remember that diarrhoea is only a symptom and the causes are numerous.  Some causes include:

  1. Intestinal upsets caused by changing food too quickly or giving/scavenging rich/fatty foods.  This is by far the most common cause.
  2. Infectious causes eg Parvovirus, Distemper, Salmonella, Campylobacter
  3. Parasites eg Giardia, worms (especially in puppies),
  4. Food allergies – if this is ongoing this will cause chronic diarrhoea and possible Inflammatory Bowel Disease
  5. Toxins eg slug bait, chocolate, insecticides
  6. Liver disease, Addisons disease, pancreatic disease and too many others to mention!

Always remember to wash your hands regularly if your dog has diarrhoea as some causes can be infectious to humans eg Giardia, Salmonella, Campylobacter, otherwise you may end up at the Doctors yourselves!



With most acute cases further tests may not be necessary, however if your dog is very unwell or the diarrhoea is chronic then tests include:

  1. Faecal tests to check for parasites, culture for bacteria, Parvovirus, presence of blood.
  2. Blood tests to check for pancreatic disease, liver disease, blood loss, protein loss etc
  3. Abdominal x-rays to get a look at the internal organs and for the presence of gas/foreign bodies/bones.
  4. Abdominal ultrasound to look at intestinal wall structure and thickness plus to look at other internal organs.
  5. Intestinal biopsies either by surgery or using an endoscope (a snake like tube with a camera attached) – this is usually only for chronic cases.



If your dog is bright, alert and well and still drinking/eating and the diarrhoea is less than 24 hours in duration, then often conservative treatment is all that is needed.  This involves feeding small volumes of a low fat highly digestible food such as chicken and rice.  Remember to use only the chicken meat (no skin, fat, bones) and use no additives such as gravy as these are high in salt. Alternatively your vet may be able to prescribe a bland food in tin/biscuit form. You need to continue to feed this diet for a day or two after the diarrhoea has resolved and then gradually mix in their normal diet.

However if your dog is unwell, seems in pain, is frequently vomiting, has very bloody faeces, has ongoing diarrhoea or has stopped eating/drinking, then it is important to visit your vet.  One of the most important therapies for diarrhoea is correcting electrolyte imbalances and dehydration, as if left untreated this can be fatal.  Your dog may need to be started on an intravenous drip.  Other treatments are numerous and will depend on the cause but may include, antacids, intestinal protectants (to line and protect the intestines), antibiotics, parasite control, and low allergen foods.   



Probably the most important way of preventing diarrhoea is to avoid sudden food changes.  If your are starting a new food make sure to slowly transition it over a few days – eg mix in a ¼ of the new food with ¾ of the old food for the first 3 days followed by ½ for 3 days, then ¾ for 3 days until you’ve changed the food, ensuring your pet doesn’t develop diarrhoea over this period.  Avoid high fat/sugary/salty foods and try to prevent your dog scavenging.  Ensure your dog is regularly treated for worms and is up to date with vaccinations as Parvovirus can be a fatal disease.

AnimalCare 2002 Limited

Animal Care Vets is actively involved in our local community. We support a number of charities, including the SPCA. We also care for the Hawkes Bay Police dogs. Our customers know by experience that they can rely on us for sound advice on treatment options and that their pet is in the very best hands with our team.