The 4 best probiotics for dogs in 2024

One of the best probiotics for dogs is VSL#3, which is also a commonly used probiotic supplement for humans. We like this supplement because it has an unusually high number of colony-forming units (CFUs). According to Dr. Mary Anne Amalaradjou, an associate professor of food microbiology in the Department of Animal Sciences at the University of Connecticut, CFUs refer to the number of live microorganisms present in a probiotic. She says it's good to aim for between 1 to 10 billion CFUs when looking for a probiotic supplement. More CFUs might not necessarily be better, but she notes that VSL#3 has been tested in both humans and dogs and has had positive effects on some conditions of the digestive system, like inflammatory bowel disease. 

Beyond its effectiveness, VSL#3 has clear storage and instructions for use: The capsules require refrigeration since live microorganisms can lose viability if stored incorrectly. This may make it difficult to transport the capsules if you're traveling with your dog.

We also don't love that VSL#3 is only offered in capsule form because this delivery method can be a hard sell with some dogs. However, this form is common among the higher CFU probiotics. Lastly, the supplement's price tag is significantly higher than other options. But, if you and your veterinarian decide that a more robust supplement is necessary for your dog, the price may be worth it.

If your dog only eats supplements that have yummy flavors, the Finn Digestive Probiotics liver-flavored chew might be one of the best dog probiotics for them. This supplement is also a good choice for dogs with food sensitivities: It's free of ingredients like wheat and chicken, although it does contain beef, which may be an allergen for some dogs. 

We like that there are added prebiotics, which may be beneficial in helping bacteria thrive in the gut microbiome. Prebiotics don't live in the gut; instead, they are consumed and help feed the probiotics already present in the microbiome. Finn's chews contain the prebiotics chicory root fiber (inulin) and fructooligosaccharide (FOS). This product is also certified by the National Animal Supplement Council (NASC), which tests animal supplements to ensure their safety.

Finn only offers this chew in one flavor, so dogs who dislike the beef liver taste may be out of luck.

A powder probiotic is a good option for dogs that dislike tablets or chews. The Vital Planet Flora Dog Probiotic is a flavorless powder that can easily be sprinkled on or mixed into your dog's food daily. 

We like that this supplement has 20 billion CFUs and all of the expert-recommended bacteria strains. It also contains the prebiotic FSO and carries the NASC quality seal.

We don't love that the powder lacks flavored options for different tastes. If you'd prefer to purchase flavored probiotic supplements, Vital Planet also makes probiotic soft chews and tablets. Exceptionally picky dogs may dislike the chalky texture of powder.

A prebiotic and probiotic combination is a smart choice when shopping for a gastrointestinal supplement, says Dr. Mike Salkin, a veterinarian with JustAnswer. Using a combination of prebiotics and probiotics may help the bacteria strains found in these products survive longer in the gut microbiome. We like that Nutramax Proviable-DC Digestive Health Supplement includes the prebiotic FSO along with seven strains of probiotics. 

Nutramax is a well-established brand that makes some of the best dog supplements, and Proviable-DC is more affordable than many competitors. It's also safe for cats, which makes it an ideal choice for multi-pet households where pets may share food.

A downside of this supplement is that it's only available in capsules, which may make it more difficult to give to your dog.

"In the simplest terms, you can call probiotics a good bug," says Amalaradjou. That good "bug" is bacteria that naturally occurs in the gut. Probiotics help you get more of these good bacteria into your dog's system, creating a more diverse internal environment. Amalaradjou says this can aid digestion. Here are a few things to consider when looking for probiotics.

Colony-forming units (CFUs): Make sure you're purchasing a product with a good number of CFUs. These are the live organisms that live in probiotics. Amalaradjou and Salkin say that, in general, products containing between 1 to 10 billion CFUs are a smart choice.

Storage instructions: Clear instructions are important to consider when shopping and should be easily accessible to the buyer, ideally on the brand's website and the package itself. For example, probiotics left for just 15 minutes in a hot car can impact their viability, so Amalaradjou recommends keeping a close eye on proper storage instructions to ensure the supplements remain viable. 

Live organisms: It's important to pay attention to the number of live organisms in a probiotic supplement. Amalaradjou says a brand should disclose how many live organisms a product will have at the end of its shelf life. 

Expiration date: The best probiotics for dogs should also have an expiration date on the package, says Amalaradjou. Expiration dates should be clearly listed on the bag, bottle, or box containing the probiotics. 

Proven bacteria strains: Amalaradjou recommends looking for probiotics that contain bacteria strains shown through research or anecdotal evidence to be effective for gut health. She provided Insider with a list of bacteria strains that are good to look out for: 

• Enterococcus faecium
• Lactobacillus acidophilus
• Lactobacillus casei
• Lactobacillus plantarum
• Bifidobacterium bifidum
• Bifidobacterium animalis

We selected the best probiotics for dogs based on the criteria shared by our experts. We evaluated products based on the presence of live bacteria strains, the number of CFUs, storage instructions, and whether the product had information about the number of live organisms. We also noted if products were flavored, their method of delivery (capsule, powder, chew), and their safety for cats.

Should I give my dog probiotics?

The best dog probiotics may be helpful for some gastrointestinal conditions and upset, but they are not a miracle supplement. "For the most part, in dogs, when probiotics are used, they are used to help with digestion to support the immune system and to maintain a healthy gut," says Amalaradjou. Both of our experts say you should consult your veterinarian before starting your dog on probiotics. It's vital to rule out any potential underlying causes that may be serious and require more intensive care. 

What is the best probiotic for dogs?

The best probiotic for dogs is the one recommended by your veterinarian. If they give you the go-ahead to start your dog on probiotics, we recommend buying a supplement that is forthcoming about all of its components. Probiotic supplements should at least name their strains and the number of CFUs, provide directions for storage, have an expiration date on the package, and disclose the number of live organisms. 

What are signs my dog needs probiotics?

According to Salkin, veterinarians and pet owners may consider giving probiotic supplements to dogs undergoing antibiotic therapy. Changes in the gut microbiome and accompanying symptoms, such as diarrhea, might indicate something is amiss. But Salkin says not to rush into buying a probiotic supplement with the hope that it will solve your dog's digestive problems. "A probiotic or prebiotic does not preclude a physical exam and testing in the form of blood, urine, and fecal testing," he says. If you suspect your dog might have gastrointestinal problems, talk to your vet first.

Do vets recommend probiotics for dogs?

Veterinarians may recommend the best dog probiotics to help ease digestive discomfort or maintain a healthy gut. Our experts say probiotic supplements may be helpful for your dog, but they should not be seen as a medication or as a solution for a potentially more severe problem.