Just like humans, the majority of a dog’s immune system resides in his gut. The gut is the largest immune organ in the body and contains approximately 70% of all immune cells. So keeping your dog’s digestive system running optimally is essential to making sure that he stays healthy, active, and lives a full and healthy life.

One way to potentially improve your dog’s digestive health is to offer him a daily probiotic supplement. There have been extensive studies on the benefits of probiotics in humans, however, veterinary research is just starting to really dive into how supplementing your pup with a variety of good bacteria can aid in keeping him healthy.

What are Probiotics for Dogs?

The World Health Organization (WHO) defines probiotics as “live microorganisms, which when administered in adequate amounts, confer a health benefit on the host.” According to American Kennel Club (AKC) veterinary expert, Jerry Klein, DVM, probiotics (bacteria or yeast) can potentially provide an array of health benefits to dogs.

“They are believed to help treat and/or prevent a variety of illnesses and diseases, especially those related to the gastrointestinal system,” he explains. They inhibit the growth and activity of harmful bacteria, such as E. coli, Salmonella, and Clostridium perfringens, as well as provide other advantages to the intestines.

Brennen McKenzie, VMD, who practices at Adobe Animal Hospital in Los Altos, California, has studied the use of probiotics in canines extensively and believes that there are definitely some benefits to dogs taking them. “In theory, if probiotics can pass through the stomach and colonize the intestines, they can have a variety of desired effects, such as preventing or treating diarrhea or improving other intestinal conditions, such as inflammatory bowel disease,” he states.

Benefits of Probiotics for Dogs

In a peer-reviewed journal, Marcella D. Ridgway, VMD, MS, DACVIM notes that there is growing evidence that supports the use of probiotics for dogs. She states that giving your dog healthy bacteria may positively impact chronic GI abnormalities, obesity, liver disease, and mood and behavior disorders. A daily probiotic supplement may also provide some ancillary benefits for dogs such as better skin and coat appearance, a reduction in gas, improved breath, a reduction of allergy symptoms, a reduction in yeast-associated disorders, and help in regulating bowel function.

Types of Probiotics for Dogs

Probiotics for dogs come in a variety of shapes and sizes. “Some are marketed just for dogs, some for a range of animals, and some for humans (that are subsequently used in dogs),” says J. Scott Weese, DVM at the Department of Pathobiology at the Ontario Veterinary College. “These can come as pills, powders, pastes, or solutions.”

Each probiotic supplement contains one or more types of bacteria and/or yeast that can carry out a variety of different functions. For instance, certain strains, such as Bifidobacterium, are known to be helpful in slowing down the duration of diarrhea in dogs and for their overall immune boosting properties. Other types, like Lactobacillus, have shown benefits in helping dogs to increase the absorption of nutrients and to optimize their digestive systems.

What to Look for in a Dog Probiotic

“There is no one probiotic supplement that is best for every dog and every health condition,” says Dr. Jennifer Coates, Veterinary Advisor for petMD. Most veterinarians carry a number of different products from trusted manufacturers and will try several before concluding that probiotics aren’t going to be helpful in a particular case. Dr. Coates reports that the following probiotic strains have some scientific evidence to support their safety and efficacy in dogs:

– Enterococcus faecium

– Lactobacillus acidophilus

– Lactobacillus casei

– Lactobacillus plantarum

– Bifidobacterium bifidum

– Bifidobacterium animalis

– VSL#3

Can I Give My Dog Probiotics Meant for Humans?

While there are no known studies that prove that human probiotic supplements can harm a dog, veterinarians that study the subject recommend that pet owners opt for a probiotic that is specially made for dogs and contains the specific strains that a dog’s gut needs. “There are significant differences in the biology of dogs and humans, including differences in the acidity of stomach fluids, digestive enzymes, and other features of the gastrointestinal tract,” says McKenzie. “Because probiotics for humans have not been designed or tested to accommodate the biology of dogs, it is impossible to know if these will be safe or effective in our canine companions. It is safer to use products designed and tested for dogs.”

How to Give a Dog a Probiotic

Canine probiotic supplements are administered orally and can be included in a dog’s food or wrapped in a treat. When administering a probiotic to a dog, it’s very important that you follow the instructions on the product label. “Each product has its own instructions which should be followed consistently,” says McKenzie. “Improperly formulated or administered probiotics can easily be destroyed in the stomach and not reach the intestines where they are intended to perform their function.”

Risks and Considerations of Probiotics for Dogs

There are not many known side effects to administering probiotics to your dog. “Probiotics are generally regarded as safe, but rare things can happen,” says Weese. “The risks to the average dog are exceptionally low and probably are only potentially relevant in very young puppies and maybe animals with highly compromised immune systems.” He stresses, however, that there are notable problems with the formulation of commercial probiotics for pets. “A few studies have shown that most commercial veterinary probiotics do not contain what they claim to contain—both the species that are present and the numbers of viable organisms,” he explains. For this reason, it is important to do your research and talk to your veterinarian to make sure that you are giving your dog a probiotic supplement from a trusted and reputable brand.

As always, talk to your veterinarian before deciding to give your dog any sort of supplement or treatment intended to help resolve health problems. “This is particularly true for probiotics, as specific manufacturing standards and appropriate dosage levels have not been established,” warns Klein. “Your veterinarian will have the best perspective on whether or not your dog may benefit from probiotics, what the best brand may be for your dog, and the appropriate dosage.”

Did you know that vitamins and supplements may help your dog with everything from joint health to immune support?