When the microbes in your dog’s stomach are disrupted or destroyed, your dog may suffer from upset stomach, constipation, diarrhea, skin conditions, allergies, and a general decline in health. The good news is that you can give your dog specially formulated probiotic and prebiotic supplements that can help to restore the balance of healthy bacteria in the gut, reducing unwanted symptoms. But dogs are not humans, so you need to purchase probiotics formulated specifically for dogs.

We reviewed dozens of dog probiotics to identify the best of the best. We’ve rounded up the top-rated, effective probiotics for dogs based on ingredients, colony-forming units (CFUs – a measure of the number of live bacteria in a product), costs, and other considerations to make it easy for you to find the perfect supplement for your beloved four-legged friend.

Our Vet’s Top Pick

NomNomNow Probiotic Support Full Spectrum

A complete probiotic and prebiotic supplement to support your dog’s digestive health.

Check Price

While researching probiotics for dogs, NomNomNow’s Probiotic Support Full Spectrum emerged as a clear standout. With 20 billion CFUs and 7 full spectrum probiotic strains per serving, plus prebiotic fiber for added bacteria development, it’s an excellent choice to support your pup’s digestive health.

The 5 Top-Rated Dog Probiotics

Editor PicksBrandRating
Our Vet’s Top PickNomNomNow’s Probiotic Support Full Spectrum n/a
Runner UpZesty Paws Probiotic Supplements for Dogs4.6
Best Budget BuyPetHonesty Probiotics for Dogs4.8
Best Probiotic Powder for DogsPurina Veterinary Diets FortiFlora Probiotic Supplement for Dogs4.6
Best Chewable Probiotics for DogsNutramax Proviable Health Supplement for Cats and Dogs4.8

*Ratings are from Amazon at the time of publication and can change

Our Vet’s Top Pick: NomNomNow Probiotic Support Full Spectrum

NomNomNow’s Probiotic Support Full Spectrum is a great supplement to help boost your dog’s overall wellness and health. This probiotic and prebiotic blend contains 20 billion CFUs and 7 full-spectrum probiotic strains per serving, including strains derived from healthy dogs. The probiotic is formulated by the NomNomNow veterinary nutrition and microbiology team. Made with human-grade ingredients at FDA-registered facilities under GMP guidelines, every batch is independently tested to ensure the integrity and high quality of the ingredients.

One bottle contains a 30-day supply. Feeding guidelines are the same for all dogs, regardless of size, and it’s safe for dogs 8 weeks and older. Simply mix one level scoop into your dog’s food once daily, reseal the bottle, and refrigerate to preserve optimal freshness.

NomNomNow Probiotic Support Full Spectrum Key Features:

  • Contains 20 billion cultures
  • Helps maintain normal digestive and immune function
  • Contains a prebiotic
  • Mix into food once daily

Our Runner Up Pick: Zesty Paws Probiotic Supplements for Dogs

Runner Up

Zesty Paws Probiotic Supplements for Dogs

Zesty Paws Probiotic Supplements for Dogs will give your dog the boost he needs in his digestion without disrupting any routines.

Help your dog feel at her best with Zesty Paws Probiotic Supplements for Dogs, delivered in a delicious soft chew that your dog can’t resist. And that yummy taste comes packed with probiotics and prebiotics for complete digestive support.

These chews are all made in FDA-registered, GMP-compliant facilities inside the United States, so you can be more confident in the freshness. And for a probiotic, freshness means effectiveness. After all, if it’s on a plane or boat for weeks after manufacturing, the active CFUs capable of reproducing their own colonies is probably less than advertised. Getting a probiotic that’s made right near your home is going to give you the best chance of the maximum CFUs.

Zesty Paws Probiotic Supplements for Dogs Key Features:

  • Great for dogs of all ages and sizes
  • 2 billion CFU per chew
  • 5 strains of probiotics and prebiotics

Best Budget Pick: PetHonesty Probiotics for Dogs

Best for Budget

PetHonesty Probiotics for Dogs

PetHonesty Probiotics for Dogs is a chew that will fix your dog’s stomach issues without breaking your bank.

The PetHonesty Probiotics for Dogs have a natural duck taste that is so good, your dogs will easily be convinced of its status as a treat, not a medicine. So you can buy this chew without having to wonder whether your dog will like it or how you’re going to be convincing him to eat it (or hide it).

There are no fillers in these chews, and that means no grains, no corn, soy, sugar, or preservatives. And more than that, it has no GMOs, either. It’s just 100% natural ingredients that give real results for your dog’s daily life. The manufacturer even donates 10% of their profits to charities that help combat learning disabilities and PTSD.

The best part, though has to be that this is at least a full month supply, even for those big dogs over 75 pounds. Quite often, those large breeds are expensive to give regular probiotics, needing three or four a day. For a smaller dog, under 25 pounds, this 90 chew bottle will give you a three month supply for your dog for less than $25, which is a huge steal! Taking in mind that this also has an overall rating of 4.8 stars on Amazon, this is a total steal.

PetHonesty Probiotics for Dogs Key Features:

  • 6 billion CFUs per serving
  • 90 soft chews
  • 4 lactobacillus strains

Best Probiotic Powder for Dogs: Purina Veterinary Diets FortiFlora Probiotic Supplement for Dogs

Best Probiotic Powder for Dogs

Purina Veterinary Diets FortiFlora Probiotic Supplement for Dogs

You can easily give your pup the probiotics he needs by sneaking the powder of Purina Veterinary Diets FortiFlora Probiotic Supplement into his daily food.

The Purina Veterinary Diets FortiFlora Probiotic Supplement for Dogs is a canine probiotic supplement that has a patent-pending formulation made by exclusively by Purina. In addition to probiotics, it contains antioxidants and other helpful ingredients.

These sachets of powder have an excellent palatability, which means your dog won’t mind the taste at all. You can sprinkle this over his food and the added taste will have him convinced you’ve actually added a treat. You can also buy a bit more and save on the 3 or 6 packs and if you really love the product, it’s even available for Amazon’s Subscribe and Save to make sure you never go without again.

With 4,600 customer reviews on Amazon and an overall rating of 4.6 stars, there’s a high probability that you’ll be one of the vast majority of satisfied customers. After all, 92% of the people who’ve tried this product can’t be wrong.

Purina Veterinary Diets FortiFlora Probiotic Supplement for Dogs Key Features:

  • Special strain of probiotic proven to promote intestinal health and balance
  • Contains antioxidant Vitamins A, E, and C
  • Proprietary microencapsulation process for enhanced stability

Best Chewable Probiotics for Dogs: Nutramax Proviable Health Supplement for Cats and Dogs

Best Chewable Probiotics for Dogs

Nutramax Proviable Health Supplement for Cats and Dogs

Nutramax Proviable Health Supplement for Cats and Dogs is a chewable probiotic that your dog will love.

Nutramax Proviable Health Supplement for Cats and Dogs was once sold only through veterinarians, pet owners can now get their hands on this powerful health supplement for both dogs and cats through Amazon. There are 7 key species of micro-floral bacteria with multiple strains, a prebiotic, and 5 billion CFUs per capsule. That’s plenty enough to make sure your dog is getting the maximum benefit to the probiotic.

For short term use where your dog is suffering big imbalances, this capsule should be given in conjunction with Proviable-KP paste. For longer term use to maintain a healthy stomach and immune system, take as is prescribed with the instructions, one capsule daily. The box comes with 80 capsules, which is close to a 3-month supply, for about $40 and for extra savings, you can Subscribe and Save. You just open and sprinkle the capsule over your pet’s food to easily administer.

With nearly 1,000 customer reviews on Amazon and an overall rating of 4.6 stars, you have every reason to take the rating at face value. And with a rating that high, there’s more than enough to tempt us.

Nutramax Proviable Health Supplement for Cats and Dogs Key Features:

  • Helps to establish a healthy digestive balance
  • Can be used alone for long-term intestinal health support and balance
  • Contains multiple species and billions of beneficial microorganisms per daily administration

Who Should Buy a Dog Probiotic

You’ve probably heard about the benefits of probiotics for human health, but did you know that your dog can benefit from healthy gut flora, too? All animals have billions of healthy microbes – “good” bacteria and yeast – in their gastrointestinal system. These microbes play an important role in many physiological processes, from aiding in the digestion of food to bolstering the immune system, warding off potential pathogens, and more. Anyone, dog or human, can notice an overall boost in their digestion and “gut” health. You may see your dog acting more puppy-like and less senior because it can heal him in ways you didn’t even know he was suffering.

There is a much more useful prevention aspect when you give a dog a probiotic, though. Because a dog is much more likely to come into contact with E. coli, salmonella, or other harmful bacteria, having an immune system full of probiotics that prevent those harmful bacteria from reproducing is a wonderful step in protecting your dog. Arming your dog’s stomach with good bacteria to fight off the bad will go a long ways for his overall health. You could take a probiotic every day for years without this every actually coming into play because the food you eat is, by and large, safe. That isn’t always the case for dogs. After all, how many times has your dog defended your realm by killing the rabbits or birds in his yard?

It could also be especially beneficial to begin a regular dose of probiotics if you want to help your dog deal with some unwanted pains or discomforts. Of course, this means if he has noticeable problems with his bowel movements (one extreme or the other can be helped by a good probiotic). As we’ve mentioned several times, a probiotic does certainly help with intestinal issues and digestion, but inside the intestine resides the bulk of your dog’s immune system. That means you’ll be hard pressed to keep your pup healthy if his bacteria is out of wack. In fact, improving his immune system may help parts of his life you hadn’t considered. A good immune system will help with inflammation and skin irritation so if he has joint pain or itches and licks a lot, you may actually see an improvement to his movement or licking with a good probiotic.

Check out our review of the best dog foods for allergies for some quality limited-ingredient and grain-free options for dogs with food sensitivities.

Our Vet’s Top Pick

NomNomNow Probiotic Support Full Spectrum

A complete probiotic and prebiotic supplement to support your dog’s digestive health.

Check Price

Important Features to Consider

A probiotic for dogs should have a few important features. Here’s what to consider when selecting a probiotic for your dog:

  • Probiotics vs. prebiotics. A probiotic is a good bacteria that can help your dog by fighting off bad bacteria and balancing his stomach. A prebiotic is basically food for the probiotics. Prebiotics will help keep the probiotics alive and kicking in the stomach and healthy enough to fight off that robust bad bacteria. Because dogs are often exposed to more aggressive harmful bacteria a prebiotic can help bolster the effectiveness of your dog’s probiotic.
  • Chews. Taste begins to play a big role for chews. It’s a useless addition to a dog’s diet if it’s not actually getting into his body. Chews have the added benefit of being used as a treat. Depending on your pup’s weight, your schedule, and the frequency of your treat distribution, you may not be able to give him the probiotic as a treat every time he does as he’s told. Check the instructions to make sure you’re not over dosing but even if he takes just one of these chews a day, it can still be given as a treat. As soon as you get home from work, for example, would be a great time to treat him for being good while you were away. Keep in mind, you’ll have to worry about the taste and chew-ability if you use them as treats. Your pup may be difficult to convince the “treat” status of this supplement if it tastes badly.
  • Powders. You can easily sneak a powder into most dog’s food without too much fuss from them and that’s a big selling point for a lot of doggy parents. They make a lot of beef or chicken flavored powders but if your dog likes his food as it is, we highly recommend the flavorless powders to prevent rocking the boat too hard, too soon. You know what they say about old dogs and new tricks and your dog may go on a hunger strike if he notices a big change to his food. If you must get a flavored kind, consider gradually working up to the full dose to make the transition easier for you both.
  • Syringes. Syringes aren’t injections like you may be fearing. They will give your dog a gel form of probiotic orally and will shoot into his mouth with such force he won’t have time to do anything but swallow it. This isn’t a method you can hide, but it could be the least struggle time overall. Your dog may not like it, but if he’s a well-behaved, obedient dog, he may just take this method like a champ and it’ll be over, from start to finish, in less than 30 seconds.
  • CFUs. CFU stands for a Colony Formed Units and it refers to the number of bacteria that are capable of dividing, reproducing, and creating their own colonies in each serving. (Note: Maybe you don’t pay close attention to all the sell by dates on your dog’s food, but you will want to pay attention on his probiotics. Over time, the number of CFUs will diminish.) There are some pretty impressive and absolute enormous numbers for CFUs; some can go up to thirteen digits. And while 100 billion is an impressive number, is it really bigger is better? The truth is, because you’re not going to “overdose” your dog in the strictest sense, you will probably never know if you’re giving him more than he needs. Any probiotic number will help, but there is a better chance of a more immediate change with the bigger numbers. The majority of dog probiotics will have around (or under) 10 billion CFUs and that will be enough to make a change in his digestion, to be sure. Just make sure you’re reading the CFUs per serving not per container. Manufacturers like to list the biggest possible number in their marketing and will often push the big, impressive “1,000+ billion CFUs!” [in every bottle].
  • Additional nutrients. If you’re already adding something to your routine, it may be a great opportunity to incorporate other nutrients from which your dog can benefit. For example, you may be able to find a multi-vitamin of sorts that also includes a probiotic. It’s not incredibly common, mind you, because the bacteria inside the probiotic may not mesh well with other ingredients. The most likely addition you’ll have in these will be complementing digestive enzymes and prebiotics. Both will help the probiotic be more effective, and are a win.

Frequently Asked Questions

What is a dog probiotic? Is it different than human probiotics?

A probiotic is a type of bacteria that does not cause your (and your dog’s) body any harm and can in fact, protect your body against harmful bacteria. They’re naturally occurring but occasionally the body will become imbalanced and that will start to have some consequences. An imbalance can cause diarrhea, inflammation, breathing issues, irritated skin, and so much more. You can give these probiotics to your dog regularly without worrying about side effects and they come in a large enough variety of forms that there will undoubtedly be a method of taking it that will work for him. There are chews, oral injections, powders, and pills, so if you struggle to get your dog to take it one way, there are certainly others to try.

Probiotics for dogs are different from probiotics for humans, so you will want to be careful with what you give your dog. No studies exist on giving dogs human probiotics, so there’s no exact answer on whether it’s safe. In all likelihood, some human probiotics would be entirely safe for your dog, but the dosage is very difficult to determine yourself. Human probiotics do tend to be a bit less expensive but you risk a lot more than a few dollars by giving your dog the wrong supplement. Mostly, you’ll risk your time. Dog probiotics have dog-specific strains of flora that will work better with their stomachs with a higher acidity.

Can a dog overdose on probiotics?

No, a dog cannot, strictly speaking, overdose on probiotics. In fact, in 2009, the National Center for Biotechnology Information (NCBI) published a study showing that dogs handled the probiotics well with no safety concerns. The bigger the CFUs, the better, generally speaking. However, there’s a good chance your dog will plateau with his benefits after a certain number. Which will be different for each dog and each specific condition you’re trying to “treat.” So you may be seeing the maximum benefits with a smaller number, and no additional benefits if you increase the CFU intake. You can experiment with this if you’d like, but to err on the side of caution: start big.

Do probiotics really work for dogs?

Probiotics absolutely can work for dogs. They can help a lot more than you may realize. But be logical; it’s not a miracle. In fact, it’s not a drug at all. If your dog has a specific and serious health concern, there’s a good chance your vet will have actual medication for him which only he can give. And those medications will probably treat your dog better than a probiotic. The probiotic can help for minor discomforts, but you will still need to talk to your vet.

That being said, if your dog has some inflammation, skin irritation, or digestive issues which your vet knows about and has said there’s not much else he can do, then a probiotic may be exactly what you need. And we know all too well how long a wait can be to get your dog into the vet. Because it’s safe to give to your dog, there’s no reason not to give the probiotic a try in the meantime and check with your vet as soon as is reasonably possible.

Can dogs take probiotics everyday?

Yes! Dogs can absolutely take a probiotic every day. The study the NCBI published in 2009 was conducted at the Procter & Gamble Pet Care Technical Center and tested the effects on dogs using probiotics for twelve consecutive weeks with absolutely no ill effects. They determined that was plenty long enough to discover if any side effects would occur and since none did, you can feel confident in your giving your dog a probiotic daily. In fact, building up a bit of a store of probiotics can help your dog’s body prevent more harmful bacteria from damaging their body as well as bolster his immune system, preventing disease, itching, and inflammation.

Jenny Jarvis