Are probiotics for dogs a good idea?

December 22, 2021 - 6 min read
This article is not intended to be a substitute for professional veterinary advice, diagnosis, or treatment. Always seek the advice of your veterinarian with any questions you may have regarding your pet’s care, treatment, or medical conditions.

Digestive disorders always make it onto lists of common health problems in dogs. If you’ve been a pet parent long enough, you’ve surely had to deal with a four-legged friend who is experiencing diarrhea, vomiting, excessive gassiness, or a loss of appetite.

The entire household’s quality of life suffers when a dog has an upset stomach, so you undoubtedly want your dog to feel better ASAP!

Many things can disrupt a dog’s normal digestion, including:

  • Eating something unusual

  • Viral or bacterial infections

  • Parasites

  • Some types of poisonings

  • Cancer

  • Pancreatitis

  • Kidney or liver failure

  • Inflammatory bowel disease

  • Gastric dilatation and volvulus (bloat)

  • Obstruction of the intestines

Some of these health problems are very serious, so if your dog has severe symptoms, call your veterinarian immediately. On the other hand, if your dog just has mild diarrhea or simply seems a bit off, it might make sense to try some home treatment while you’re waiting to see if a trip to the vet’s office is really necessary. Probiotics can play a role in that home treatment.

Dog lying down

What Are Probiotics for Dogs?

Probiotics are living, beneficial microorganisms — bacteria and yeast — that are normally found in a dog’s GI tract. Probiotic supplementation gives you a way to boost the number of these “good” microbes in your dog’s gut.

Probiotic microorganisms living within your dog’s intestinal tract perform many important functions. They help with digestion, make important vitamins and other substances that dogs need to stay healthy, help maintain the immune system, and even play a role in your dog’s mood.

The term “probiotic” is used to describe many different strains of good bacteria and yeast, some of which are more effective than others in managing certain health problems. For example, Bifidobacterium longum BL999 is used to help dogs stay calm while Enterococcus faecium is a better option for dogs with diarrhea. It can be hard to figure out which probiotic supplement is right for your dog, or even if a probiotic should be used at all, which is why it’s always best to talk to your veterinarian before starting your dog on a probiotic supplement.

Dogs and parent outside

Why Are Probiotics Important?

Dogs require probiotics, but these important microorganisms are already in your dog’s gut. Do you need to give your dog a supplement? Which strains would be most effective? Do probiotics really work at all?

Unfortunately, these questions haven’t been definitively answered. Some studies indicate that certain probiotic strains may help resolve acute diarrhea or in the long-term management of chronic conditions, but other research casts doubt on whether probiotic supplements are effective at all. Thankfully, probiotics are very safe, so if you and your veterinarian decide to give them a try, you don’t have to worry about making the situation worse rather than better.

Dog with carrot

Why Are Prebiotics Important?

Probiotic supplements aren’t the only way to boost the number of “good” microorganisms in a dog’s gut.  Prebiotics are indigestible parts of foods like vegetables, whole grains, fruits, and legumes. Beneficial microorganisms in the gut ferment prebiotic fiber sources to stay healthy and reproduce. Prebiotic supplements are available, and they are often included in probiotic supplements as well. Look for ingredients like fructo-oligosaccharides, beet pulp, chicory, arabinogalactan, or inulin.

Dog sitting down

When Should You Give Your Dog a Probiotic?

Diarrhea is the most common problem that leads pet parents and veterinarians to give dogs probiotics. Say your dog has been on antibiotics or recently raided the garbage can and now has diarrhea. Giving your dog a probiotic supplement for a few days may help that diarrhea resolve more quickly than it would otherwise. Probiotics can also be given in advance of a stressful situation that typically gives a dog diarrhea.

Probiotics may also help in the management of chronic digestive disorders, like inflammatory bowel disease, but long-term administration is usually necessary. Extended treatment is also required when using Bifidobacterium longum (BL999) to help dogs stay calm.

Immune support and overall health are other reasons why some dogs are put on probiotics. Why? As odd as it may sound, most of the immune system resides in the gut, so a healthy digestive tract is essential to good immune function. Research indicates that changes in the gastrointestinal tract’s microbiome “may impact not only GI disease, but also allergies, oral health, weight management, diabetes, and kidney disease.”

Do healthy dogs need a probiotic supplement? Probably not. There’s no good evidence that they’d provide much of a benefit. If your dog’s natural gut microbiome is functioning at a high level, why mess with it!

Happy puppy

What Are the Benefits of Probiotics?

Sometimes a dog’s resident probiotic microorganisms need a boost to help out-compete bad actors within the gut that secrete toxins or disrupt healthy digestion. Bacterial imbalances within the natural gut microbiome can lead to:

  • diarrhea

  • excess gas

  • irregular bowel movements

  • immune system dysfunction

  • mood disorders

Probiotic supplements may help with all of these, but don’t just give your pup random probiotics. Different probiotic products are made for different purposes. Do your research beforehand and read information labels closely before buying.

Probiotics that are designed specifically for pets and have dosing instructions for dogs are the easiest to use. Reach for these products first if you are going to give your dog a probiotic. Probiotics commonly recommended by veterinarians include:

  • Fortiflora and Proviable-DC for long term use

  • Proviable-KP combined with Proviable-DC for acute diarrhea

  • Purina Pro Plan Veterinary Supplements Calming Care for behavioral problems

  • VetriScience Laboratories also makes several different types of high-quality probiotics.

Probiotics designed for humans can be given to dogs under certain circumstances, but it’s safest to do so when a specific probiotic has been recommended by your veterinarian.

Dog sleeping

What Are the Different Probiotic Strains?

Probiotic supplements are all different. Some contain just one type of microorganism while others contain numerous strains of probiotics. The number of living microorganisms per dose—measured in CFUs (colony forming units)—and the amount of scientific evidence supporting the use of various strains also varies wildly.

The following strains of probiotics have at least some scientific support for use in dogs:

  • Enterococcus faecium

  • Lactobacillus acidophilus

  • Lactobacillus casei

  • Bifidobacterium animalis

  • Bifidobacterium bifidum

  • Lactobacillus plantarum

  • Saccharomyces boulardii

  • VSL#3

  • Bifidobacterium longum (BL999)

This is not a complete list, and new research is being performed all the time, which is why it’s always a good idea to consult with your vet before purchasing a new probiotic for your dog.

Dog on leash looking up at parent

Forms of Probiotics for Dogs

You don’t just have to worry about what probiotic strains are included in your dog’s supplement. How the microbes are delivered is also important. They’ll only work if they survive manufacturing, transport, storage, and the early stages of digestion and your dog is willing to take them!

Probiotics come in many forms. The best option for your dog will include the microorganisms they need in a formulation they enjoy taking.


  • Powders are a popular option because they can include large numbers of microorganisms and can be sprinkled on or mixed in regular dog food. Some powdered probiotics are flavored to make them even more attractive.

  • If your dog tends to be turned off by changes to their diet, another option might be better for them.

Pills and Capsules

  • Picky eaters or dogs who can’t tolerate a change to their diet tend to do well with capsules or pills.

  • Hiding pills and capsules in yummy treats or using a pill popper can make it easier to get your dog to take their probiotic.


  • Many dogs love probiotic chews that taste like treats.

  • However, some chews contain low numbers of probiotics, and giving your dog too many can lead to weight gain or dietary imbalances.

Dog Food

  • Some commercially available dog foods are supplemented with probiotics.

  • If you’re going to make a dietary change, do it slowly to avoid disrupting your dog’s digestive health. Quickly switching to a new food may lead to more problems than it solves, at least in the short term!

  • Probiotic-rich food may be a good option if you were already looking to change your dog’s food, but make sure the diet you choose provides complete and balanced nutrition for your dog’s life stage.

What About Yogurt?

  • People who are looking to boost their probiotic intake often turn to yogurt. Does it work for dogs too?

  • The answer isn’t a simple one. Some dogs, like those who are lactose-intolerant, react poorly to yogurt. Also, you would have to feed a lot of yogurt to your dog to provide anywhere near the number of probiotic organisms that a high-quality supplement can. A dollop on top of their dog food isn’t going to do much.

  • If you want to give your dog yogurt, make sure that it contains live cultures and is plain and unsweetened. Talk to your vet before incorporating large amounts of yogurt into your dog’s diet.

Dog on walk

DIY Probiotics

Yogurt isn’t the only food that contains probiotics. Fermented foods like kimchi, sauerkraut, real buttermilk, kefir, and soft cheeses all contain probiotics too. But many of these aren’t a good option for dogs either because dogs don’t like the taste, they contain potentially dangerous ingredients like onion or garlic, or they are high in fat, which can lead to pancreatitis.

Dog on leash sitting outside

Side Effects of Dog Probiotics

Supplements designed specifically for canines are the safest way to add probiotics to your dog’s diet. If you follow the dosage instructions provided on the label, you’re unlikely to run into any problems.

However, it is possible for a dog to experience side effects from probiotics, particularly when supplementation first starts or if they are put on a very high dose. Side effects may include:

  • Excess gas

  • Loose stool

  • Constipation

  • Abdominal discomfort

  • Poor appetite

These symptoms will usually resolve after a few days. If they are severe, stop giving your dog the probiotic supplement and talk to your veterinarian. They may recommend reducing the dose or trying a different product.

Dog lying down with tongue out

How and Where to Buy High-Quality Probiotics

Probiotics are classified as nutritional supplements, which means they are not very tightly regulated in the United States. Unfortunately, some of the probiotics available for purchase are made by disreputable companies that produce inferior products. Here are some tips for buying high-quality probiotics and avoiding products that are a waste of your money:

  • Consult with your veterinarian. They can have experience with good probiotics made by reliable manufacturers.

  • Only purchase probiotic supplements that provide all the information you need to make an informed decision on the product label or through their websites. It should be easy to learn what probiotic strains are included, how many CFUs they contain, whether prebiotics are present as well, and whether there are any scientific studies to support the product’s use.

  • Look for a National Animal Supplement Council (NASC) quality seal, which indicates the company has successfully passed an independent third-party audit every two years and complies with numerous quality-control measures and labeling guidelines.

  • Avoid supplements that are made by fly-by-night companies. Choose products made by manufacturers with a long track record of making quality products.

  • Make sure you’re buying from a trustworthy source. The best places to buy probiotics are veterinarians’ offices and pet stores and online pharmacies that have earned a good reputation.

  • Don’t make a change without first consulting with your vet. Different products are used to treat different problems and you don’t want to inadvertently pick the wrong type.

Dog and cat together

A Wellness Plan Can Help You Pay for Supplements (Including Probiotics)

Cost is probably not a big concern if you’re just looking to treat your dog with a probiotic for a few days to help them get over a short bout of diarrhea. But if your dog has been diagnosed with a chronic health condition and probiotics are part of their long-term care, the expenses can really add up.

Always start by giving your dog’s probiotic at the dosage recommended on the label or by your veterinarian. This lets you see what the product’s effect can be. After a month or two (and with your veterinarian’s permission), you can try experimenting with a lower dosage. Instead of daily administration, perhaps you can give your dog a capsule every other day and maintain the same benefits. Prebiotic supplementation may also help increase the effectiveness of your dog’s probiotic.

Thankfully, good pet insurance companies will help pay for the cost of probiotics when they are part of a veterinarian-recommended treatment plan. Some even offer wellness plans—like this one—that will help reimburse you for supplements, including probiotics, that are part of a dog’s preventative care.

Jennifer Coates, DVM
Veterinarian, Veterinary Writer, Editor, and Consultant

Dr. Jennifer Coates is a writer, editor, and consultant with experience in veterinary medicine, science, animal welfare, conservation, and communications. She has written for outlets including petMD, Chewy, and ManyPets.