Glossary

Probiotics

Live beneficial microorganisms given as supplements or in food that may help some dogs with digestive upset, though products vary a lot.

Also called: probiotic for dogs, gut bacteria supplement, canine probiotic, Enterococcus faecium, Bifidobacterium

Probiotics are live microorganisms, such as certain strains of Enterococcus, Bifidobacterium and Lactobacillus, that are meant to support the balance of bacteria in the gut. Studies suggest particular strains can help some dogs with diarrhea, especially stress colitis or after antibiotics, but benefits depend on the exact strain, and results do not carry over from one product to another.

Quality also varies. Pet supplements are not regulated like drugs, and some contain fewer live organisms than the label claims, or different species. Human products and fermented foods such as yogurt are not equivalent, and some contain sweeteners that are dangerous to dogs.

A prebiotic is a fiber that feeds helpful bacteria, and a postbiotic is a product the bacteria make. Ask a veterinarian before starting one, especially if a dog is young, has a weak immune system or has ongoing diarrhea.

Last reviewed November 8, 2026

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