Inconsistent stool, apparent upset stomach, and bloating—among other signs of digestive discomfort in dogs—may potentially be reduced or improved with a probiotic supplement. Probiotics are supplements that contain "good" bacteria meant to improve your dog’s gut flora. Dog probiotics have a variety of claimed beneficial effects, such as reduced gas and firmer stools.
But while probiotics have exploded in popularity and are generally safe for use, data on their efficacy is limited and positive results for your dog are not guaranteed, particularly if your dog is already healthy. While some evidence suggests the wider usefulness of probiotics, your dog is most likely to benefit if they have specific health needs.
“Probiotics may have slight beneficial effects on immune function,” Patrick Carney, DVM, PhD, DACVIM (SAIM), assistant professor of community practice at Cornell University's College of Veterinary Medicine, told The Spruce Pets.
Dr. Carney also cited inflammatory bowel disease as a condition where your dog may benefit from probiotic supplements. “If looking to treat a specific disease, working with a veterinarian to choose a product would be the smart way to go.”
If you decide that probiotics are right for your dog, our favorite is Purina Fortiflora Canine Nutritional Supplement, which is designed to treat common gastrointestinal issues like diarrhea. It comes in single-use sachets that are easy to incorporate into your dog’s normal feeding routine. We also recommend several other probiotic supplements that may better match your and your dog’s needs.
Here are the best probiotics for dogs.
Purina Pro Plan Fortiflora Canine Probiotic Supplement
Easy to use
Well-researched bacteria for gut flora
Liver flavor can change taste of your dog's food (some dogs love it, some don't)
Purina Fortiflora Canine Nutritional Supplement comes in pre-measured packets, making it easier to ensure that your dog is getting a daily dose of probiotics. Designed to be sprinkled over your dog’s food, Fortiflora is liver-flavored, making it irresistible to most dogs. The Purina probiotic supplement powder also provides vitamin E, protein, and antioxidants.
Fortiflora is meant in particular for puppies and adult dogs with diarrhea problems. It can also help reduce flatulence. According to Purina, Fortiflora uses a specific strain of Enterococcus faecium, a bacteria commonly found in human and animal digestive systems. Enterococcus has several cited advantages, including hardy growth that crowds out disease-causing bacteria like E. coli and its long history of reliable use in probiotic research.
Purina Fortiflora is sold in packs of 30, providing you with a month’s supply. A chewable version is also available.
Price at time of publish: $31
Formulation: Powder | Quantity: 30 sachets | CFUs: 100 million | Ingredients: Enterococcus faecium, L-ascorbyl-2-polyphosphate (source of vitamin C), brewer's dried yeast, vitamin E supplement, zinc proteinate, beta-carotene, salt, manganese proteinate, ferrous sulfate, copper proteinate, calcium iodate, sodium selenite
CFU stands for colony-forming units, which is the number of alive and active microorganisms in one serving of a probiotic dietary supplement.
NaturVet Advanced Probiotics & Enzymes Plus
Stomach enzymes in addition to probiotics
Blend of two different well-tested bacteria colonies
From a regularly audited company with reliable track record
Chews are a little squishy and unpleasant to handle
NaturVet’s Advanced Probiotics soft chews include Bacillus subtilis, a durable bacteria found in the digestive systems of cows and humans that may contribute to healthier gut flora. It also contains Bacillus coagulans, a probiotic approved for veterinary use by the U.S. Food and Drug Administration that's been demonstrated to improve nutrient digestibility (and is even used in the treatment of human digestive disorders like IBS).
But the NaturVet chews offer more than beneficial gut flora. They also incorporate supplemental stomach enzymes, including protease and cellulase, which aid in the breakdown of meat and vegetable materials in your dog’s food. It's a comprehensive approach to fortifying your dog's digestion as much as possible.
While many supplement makers can be frustratingly opaque, NaturVet is a subsidiary of Swedish pet healthcare company Swedencare and takes a number of steps to verify the quality of its supplements, including compliance with FDA Current Good Manufacturing Practice (CGMP) regulations, with regular third-party audits by U.L. Labs and certification from the National Animal Supplement Council.
NaturVet Advanced Probiotics are also available in powder form if you’d prefer to use it as a direct mealtime supplement.
Price at time of publish: $29
Formulation: Chews, but powder version also available | Quantity: 70-, 120-, and 240-count | CFUs: 100 million Bacillus coagulans, 1 billion Bacillus subtilis | Ingredients: Brewer’s yeast, glycerin, dried potato product, flaxseed, lecithin, canola oil, calcium sulfate, maltodextrin, tapioca starch
Fera Pet Organics USDA Organic Probiotics with Prebiotics
USDA organic ingredients
Tasteless and odorless
Vegan and gluten-free
Safe for cats too
Requires measured scoops
This vet-formulated scoop-and-serve, ultra-fine powder is packed with pre- and probiotics. You’ll find an impressively high number of strains; there are 12 different strains in total, which surpasses the number found in most pet probiotic products. The ingredients are certified USDA organic, third-party tested, and made in GMP-registered facilities.
You won’t find additives, fillers, or anything potentially iffy or synthetic in this product, either. The formula is tasteless, odorless, and colorless, making it extra simple to mix into your dog’s food undetected; for this reason, it’s a win for many pet parents who have picky eaters on their hands. In addition to supporting general gastrointestinal wellness, this product is formulated to help lessen bad breath and diarrhea.
This powder formula is safe for use in both dogs and cats, which offers additional savings and convenience to multi-pet households. It’s also shelf-stable, so you don’t have to clear room in the fridge or worry about it spoiling in the pantry.
The Fera Pet Organics powder is loaded with 12 strains of probiotics, with each scoop delivering 5 billion CFU.
Price at time of publish: $25
Formulation: Powder | Quantity: 2.5 ounce) | CFUs: 5 billion per scoop | Ingredients: FOS (fructooligosaccharides), organic inulin derived from agave, organic acacia, Lactobacillus acidophilus, Lactobacillus casei, Saccharomyces boulardii, Lactobacillus plantarum, Bifidobacterium infantis, Enterococcus faeciuim, Lactobacillus bulgaricus, Bifidobacterium bifidum, Bifidobacterium longum, Lactobacillus rhamnosus, Lactobacillus brevis
Best for Older Dogs
Amazing Nutritionals Probiotic Joint Chewable Tablets
Designed specifically for joint health
Appealing liver plus bacon flavor
Tablet less chewy and appealing than many other chews
As your dog ages, new problems may begin to pop up. Tackle any developing digestive dilemmas and ease joint pain with a probiotic for senior dogs, like Amazing Nutritionals Probiotics Joint Formula.
This supplement is for dogs who suffer from arthritis, joint pain, and stiffness. It omits many of the most common allergens for dogs, including wheat, corn, soy, egg, gluten, and more but includes 7 billion CFU of beneficial bacteria. In addition, your dog will get a dose of MSM, chondroitin, and glucosamine to ease any arthritis and support joint and cartilage health. It's also supplemented with stomach enzymes to bolster digestion.
Amazing Nutritionals Probiotics Joint Formula is made in the United States in a GMP organic-certified facility.
Price at time of publish: $30
Formulation: Chewable tablet | Quantity: 120 count | CFUs: 7.5 billion Lactobacillus acidophilus per chew | Ingredients: Amylase, lipase, protease (stomach enzymes), glucosamine sulfate, chondroitin sulfate, MSM methylsulfonylmethane, dicalcium phosphate, liver, stearic acid, whey, bacon flavor, magnesium stearate, silicon dioxide
Best for Digestion
Zesty Paws Probiotic Bites with Natural Digestive Enzymes Chews
Uses a pumpkin base, which has been commonly recommended for digestive issues
High CFU load of six different probiotics
Not every dog loves pumpkin
If your dog is experiencing digestive distress or frequent tummy trouble, a probiotic with digestive enzymes may help to ease digestion and regulate elimination. Zesty Paws Probiotic Bites not only contain the probiotic load and supplemental stomach enzymes seen in several other products we recommend but also incorporate a more old-school doggy digestive aid: pumpkin. The high-fiber squash has long been recommended by veterinarians for digestive issues and forms the basis for these chews.
Each Zesty Paws chew has over 3 billion CFU of six different probiotic strains, which is equivalent to some prescription-strength probiotics. In addition to its primary pumpkin ingredient, Zesty Paws chews also incorporate papaya, which is high in folate and vitamin C. Together, these two additives may help your dog properly digest and eliminate food.
The one downside may be the taste. Some dogs scarf pumpkin, but others are indifferent. If your dog is uninterested, try crumbling up a chew and using it as a food topper instead.
Price at time of publish: $29
Formulation: Chewable | Quantity: 90-, 180-, 270-count | CFUs: 3 billion CFU per chew, including Bacillus subtilus, Lactobacillus acidophilus, and four other strains | Ingredients: Pumpkin, papaya, pea flour, palm fruit oil, garbanzo flour, tapioca flour, flaxseed meal, sunflower lecithin, natural vegetable flavoring, coconut glycerin, rosemary extract
Best for Puppies
The Honest Kitchen Daily Boosters Instant Goat's Milk with Probiotics
Easy to prepare
Can be served alone or as a food topper
Can also be served to cats
Hard to keep mixture from getting a little lumpy
Serving size is too large for puppies
Must be mixed every time
Support a healthy gut from an early age by introducing an easy-to-digest probiotic like The Honest Kitchen's Daily Boosters Instant Goat's Milk.
Each half tablespoon of Daily Booster goat milk contains 1.25 billion CFU of four different strains of healthy bacteria. The dehydrated supplement is made to human-grade food standards, using goat's milk from pasture-raised goats. Approved by the National Animal Supplement Council, The Honest Kitchen's probiotic powder doesn't use any preservatives, GMO ingredients, corn, wheat, or soy.
What makes this goat milk Daily Booster so useful for puppies is that it can be used as an easy food topper or provided as a hydrating bowl of liquid. Preparation is easy: Simply mix well with warm water. The probiotic milk is then ready to be poured over food, enhancing your active puppy's hydration.
The Honest Kitchen Daily Boosters are available in a dry powder jar or in single-serving packets. One downside for puppy owners is that the serving size is calibrated for a 25-pound dog, so you'll likely have to measure out a smaller serving for your puppy.
Price at time of publish: $17
Formulation: Powder, individual packets | Quantity: 5.2-ounce jar, 12-count single servings | CFUs: 1.25 billion CFU per chew, including Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus rhamnosus, and Bacillus coagulans | Ingredients: Dehydrated goat's milk, dried Aspergillus oryzae fermentation product, dried Aspergillus niger product, dried Trichoderma reesei fermentation product, dried pineapple fermentation product
FloraZil+ Multi-Probiotic Food Spray For Dogs
Spray bottle is easy to use
No need to refrigerate
Strong odor may not be popular with your dog
If you’re looking for the simplest way to give your dog a daily dose of probiotics, a spray formula is hard to beat for convenience. The FloraZil+ Multi-Probiotic Food Spray is our choice for a probiotic spray that is easy to dispense while supplying beneficial bacteria for your pet.
This probiotic spray for dogs doesn’t need to be refrigerated, so store it in the place that is most convenient for you. Each milliliter of the liquid formula contains a minimum of 350,000 CFU of probiotics. The number of sprays in a single dose of the formula depends on the size of your dog, with smaller canines getting up to three sprays at a time and larger dogs getting anywhere from four to six sprays per meal.
If measuring or mixing a supplement into your dog’s meal isn’t compatible with your daily routine, then FloraZil+ Probiotic Spray for dogs is a simple solution to support your dog’s gut while keeping things easy.
Price at time of publish: $17
Formulation: Spray | Quantity: 6 ounces | CFUs: 350,000 CFU per spray | Ingredients: Water, liquid Lactobacillus plantarum fermentation product, liquid Enterococcus thermophilus fermentation product, liquid Lactobacillus casei fermentation product, liquid Bifidobacterium bifidum fermentation product, liquid Bifidobacterium animalis fermentation product, liquid Bacillus subtilis fermentation product, liquid Lactobacillus bulgaricus fermentation product, liquid Bifidobacterium longum fermentation product, active dry yeast, cane molasses, salt, natural flavor.
Best Sprinkle Capsule
Nutramax Proviable-DC Digestive Health Supplement
Convenient capsule can be pilled or sprinkled
Safe for cats too
Seven strain formula
Capsules made from animal byproduct gelatin
While not a powder in the traditional sense, this break-apart capsule offers a powder-like, sprinkle-friendly interior. Simply open the capsule and deposit the small, pellet-like contents in your pup’s food bowl for a virtually taste-free bacteria boost. The formula is brimming with good bacteria, incorporating seven different strains. Moreover, each capsule offers 5 billion CFU per serving. In addition to gut-regulating probiotics, which may help with digestive issues related to stress and diet changes (and thus may abate unpleasantries like loose stool and vomiting), these capsules also contain prebiotics, which essentially function as “food” for the good bacteria to thrive and work their best.
This formula is safe to use for both dogs and cats, making it a convenient option for multi-pet households. For what it is, the value for money is ideal, too. Lastly, this pill can be used in short-term scenarios as well as every day over the long term, depending on your pet’s specific needs.
Price at time of publish: $44
Formulation: Sprinkle-friendly capsules | Quantity: 30 or 80 capsules | CFUs: 5 billion CFU per capsule | Ingredients: Enterococcus faecium, Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus bulgaricus, Lactobacillus casei, Bifidobacterium bifidum, Lactobacillus plantarum
Purina Fortiflora Canine Nutritional Supplement is our overall favorite. It comes in pre-measured packets, making it easy to give your dog the correct daily dose of probiotics. If you're looking for a chew instead, check out NaturVet’s Advanced Probiotics Soft Chews, which include stomach enzymes to further aid digestion and are manufactured in a third-party audited facility.
What to Look for in Probiotics for Dogs
Ease of Use
Probiotics for dogs come in different formulations, including powders, capsules, tablets, chews, and even sprays. Individual dogs may accept one formulation more readily, for instance, a powder mixed into the food. Chewable products can also be convenient, though individual dogs might not like the taste of every chew. Some powered probiotics for dogs come in pre-measured doses, eliminating the need for measuring spoons.
Always choose probiotics made specifically for dogs to ensure the product contains the correct strains of beneficial bacteria. Look for probiotic products that contain a guaranteed level of live microorganisms.
The advice that we got from Patrick Carney, DVM, PhD, DACVIM (SAIM), assistant professor of community practice at Cornell University's College of Veterinary Medicine is “Stick to those [products] with more research, which tend to be the ones from well-known veterinary manufacturers.”
Because probiotic products for dogs contain living organisms, they must be stored properly to keep the good bacteria alive. Follow all instructions on the product label. Some probiotics must be stored in the refrigerator, and all should be kept cool and dry and away from overly warm temperatures. Always look at the use-by date on the package. As with human supplements, probiotics for dogs should include a clear expiration date. Bacteria that comprise probiotics are live, of course, so it’s important to ensure they’re still viable.
The size and weight of your dog will determine the proper dosage amount for most probiotics, with smaller dogs requiring less than larger canines. The recommended serving should be included on the label of the probiotic you select. Going above the recommended amount may lead to digestive discomfort and giving less may not deliver the intended benefits of the probiotic.
Can you give a dog probiotics to help with diarrhea?
Probiotics can be helpful for dogs suffering from diarrhea, especially diarrhea caused by stomach upset from switching foods abruptly, diarrhea caused by stress or anxiety, and diarrhea that occurs after using antibiotics. However, it’s important to see a veterinarian to find out what is causing your dog’s diarrhea, as probiotics alone cannot always resolve diarrhea, and your dog may need further tests or treatment. Always talk to your veterinarian before starting any supplement, including probiotics.
Is yogurt a good probiotic for dogs?
Small amounts of plain, unsweetened yogurt may provide dogs with some beneficial bacteria that might help improve digestion and gut health, but there's no scientific evidence to back this up. Large amounts of dairy, including yogurt, can cause stomach upset in dogs, so give no more than 1 to 3 teaspoons of yogurt per day, depending on whether your dog is small, medium, or large.
Can dogs take human probiotics?
In most cases, human probiotics do not pose a risk to dogs, but Dr. Carney does not recommend this approach.
“The majority of human probiotics do not seem to survive transit through the canine gastrointestinal tract,” he said. “So I do not recommend using human probiotics—they are not likely to be harmful, but are also very unlikely to provide any benefit. If using a probiotic, I would recommend a veterinary-specific product.”
What do probiotics do for dogs?
Early research suggests that probiotics may aid in digestion and relieve a bevy of discomforts, including diarrhea and other stool irregularities.
“The level of research behind veterinary probiotics varies widely,” Carney told The Spruce Pets. In fact, he notes, “Anyone can package any bacteria and call it a veterinary probiotic!”
As such, it's important to seek out trusted brands with transparent manufacturing practices.
Why Trust The Spruce Pets?
Sophie is a freelance writer and product tester for The Spruce Pets. For this article, she consulted Dr. Patrick Carney, DVM, PhD, DACVIM (SAIM), assistant professor of community practice at Cornell University's College of Veterinary Medicine, regarding what to look for when shopping for a probiotic for dogs and whether probiotics made for dogs are substantially supported by scientific evidence.
A previous version of this article was written by Erica Puisis, a freelance writer who has contributed to The Spruce since 2017. To make this list, she considered each pick's recommended age, type, and use.