Approximately one in every 12 dogs in the U.K. will be diagnosed with diarrhea each year, with some breeds more susceptible than others, according to a study published June 11, 2025 in the open-access journal PLOS One by Dan O'Neill from the Royal Veterinary College, U.K., and colleagues.
For this new study, researchers analyzed the health records of more than two million dogs brought to the vet in the U.K. in 2019. They estimated that 8.18% of them, or about 1-in-12, were diagnosed with diarrhea at some point during the year.
But six breeds — Maltese, Miniature Poodle, Cavapoo, German Shepherd, Yorkshire Terrier, and Cockapoo — were significantly more likely to be diagnosed with diarrhea than generic crossbreeds. Just two breeds, Jack Russell Terrier and Chihuahua, were less likely to be diagnosed with diarrhea. It's possible that these breeds have higher and lower predispositions to diarrhea. Alternatively, the authors of the new study speculate, different breeds could also have different diets and exercise habits, or even owners with different likelihoods of taking their dog to the vet in the first place.
Dogs which were three years old and younger, as well as dogs aged nine and over, were more likely to be diagnosed with diarrhea than dogs four to five years old. Young dogs may be more likely to eat things they shouldn't, giving them digestive issues, and older dogs may suffer diarrhea from the complications of aging, the authors suggest. In addition, many of the dogs with diarrhea were diagnosed with other conditions at the same time. About 44% had vomiting, 28% had a reduced appetite, and 24% were lethargic — and approximately 29% of all cases were classified as hemorrhagic, or bloody, diarrhea.
Most dogs appeared to recover quickly from their diarrhea, with more than 80% needing just one visit to the vet. Despite this, the study found that around 38% of all diarrhea cases were treated with antibiotics, even as experts recommend against antibiotic use in dogs with mild or moderate diarrhea.
Dr. Dan O'Neill, Associate Professor of Companion Animal Epidemiology at the RVC and co-author of the paper, adds: "Experiencing the dreaded "poonami" with your dog is one of those events any dog owner fears. This new study shows that diarrhea events are very common in dogs but that owners should not panic – no matter how bad the deluge, most dogs will recover in a few days after veterinary treatment."
In your coverage, please use this URL to provide access to the freely available article in PLOS One: https://plos.io/3Fe2GYJ
Citation: O'Neill DG, Prisk LJ, Brodbelt DC, Church DB, Allerton F (2025) Epidemiology and clinical management of acute diarrhoea in dogs under primary veterinary care in the UK. PLoS One 20(6): e0324203. https://doi.org/10.1371/journal.pone.0324203
Author countries: U.K.
Funding: This study was supported at the RVC by an award from the Kennel Club Charitable Trust and Agria Pet Insurance. Neither the Kennel Club Charitable Trust, Agria Pet Insurance nor the Kennel Club had any input in the design of the study, the collection, analysis and interpretation of data or in writing the manuscript.
