Whether it’s a one-off splatter or an ongoing issue, diarrhoea is the gut saying ‘no thanks.’ From parasites to stress, here’s what’s behind your dog’s runny toilet habits.
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Our Top 10 must-knows about dog diarrhoea




















Diet Change: A new food - especially one with grains or different proteins - can cause loose stools, as the gut microbiome reacts to ingredients it hasn’t seen before.
Food Intolerance: Some dogs can’t digest chicken, wheat or dairy. Their guts respond with soft stools, bloating, and loud stomach gurgles within hours of eating.
Parasites: Giardia, whipworms and roundworms damage the gut lining. The result? Explosive or mucousy diarrhoea, often with weight loss and scooting behaviour.
Stress: Boarding kennels, loud noise, or guests at home can trigger stress colitis. The stool may be soft, urgent, and coated with slime - but the dog otherwise seems well.
Bacterial Infections: Bugs like E. coli or salmonella can trigger sudden diarrhoea. Dogs may act off-colour, have a mild fever or pass stool that’s green and very watery.
Antibiotics: Gut flora disruption during treatment leads to soft or runny poo, especially if probiotics aren’t used. It often resolves after the course ends.
Exocrine pacreatic insufficiency: The pancreas fails to release enzymes, leading to yellow, greasy diarrhoea and extreme hunger with weight loss in affected dogs.
Toxicity: Slug pellets, garbage, or spoiled food can cause violent diarrhoea as the body tries to flush the poison fast—often with vomiting and shaking alongside.
IBD Flare-up: Inflammatory Bowel Disease causes long-term gut inflammation. Flares involve diarrhoea, mucus and weight loss, and need medication - not just diet changes.
Parvo Virus: This deadly disease causes bloody, foul-smelling diarrhoea and rapid collapse in unvaccinated puppies. Seek emergency help immediately if suspected.
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Summary of this article
Diarrhoea isn’t always simple. Watch for blood, lethargy or repeat episodes.




From the experts: Diarrhoea lasting over 24 hours, especially with blood, vomiting or lethargy, is a veterinary issue. In puppies, dehydration can escalate within hours.




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