Probiotics are live bacteria that may help control and manage the gut microbiome, and support normal stool formation. The evidence in dogs shows modest benefits for acute (severe) digestive upset, though results vary considerably between individuals.
In controlled trials, dogs receiving canine-specific probiotic combinations during acute upset showed improved stool consistency, with time to normal stools averaging 1.3 days compared to 2.2 days in placebo groups (1). However, for chronic loose stools, dietary management typically remains the primary factor, with probiotics offering variable additional support.
Strain matters more than marketing
Not all probiotics work the same way. Bacillus subtilis C-3102 has been associated with firmer stools and improved nutrient digestibility. Multi-strain products containing Lactobacillus and Bifidobacterium appear in veterinary studies for gut support. Choose products with named strains (not just species) and clear CFU counts—typically 10^8 to 10^10 CFU per day for dogs, depending on their weight.
If loose stools persist beyond 48 hours, or your dog shows vomiting, lethargy, or blood in stools, probiotics alone aren't sufficient - they need a check-up from a vet.
This content is for general information only and does not replace veterinary advice. Supplements and nutritional products are not licensed veterinary medicines. Always speak to your vet before making changes to your dog’s diet, supplements, or care routine.
