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6 Best Probiotics for Dogs With Diarrhea and Allergies (Top-Rated & Reviewed)

Probiotics may help relieve common gastrointestinal upset and disorders in dogs.

Probiotics may help relieve common gastrointestinal upset and disorders in dogs.

Why Are Probiotics Important for Your Dog's Health?

Let’s face it. Dogs eat all kinds of nasty things when we aren't looking. In fact, gastrointestinal disorders are the second most common health issue for dogs after skin conditions according to Pet WebMD. When Fido is having emergency gastrointestinal issues (non-life threatening), a good dose of dog-approved probiotics can quickly correct loose stool and diarrhea.

Whether your dog suffers from ongoing food allergies or gas and the occasional upset stomach, probiotics are a natural and healthy way to replenish good gut flora in the digestive system. The health of the gut is recognized as an important component of the overall health of the immune system, and probiotics work by introducing beneficial bacterial strains into the intestinal tract. Good gut health allows the intestines to remove toxins from the body, and specific bacteria aid in the absorption of beneficial nutrients.

Owner reviews also demonstrate that probiotics can alleviate many canine skin disorders. As the market for canine supplements is burgeoning, we took a look at some of the top-rated probiotics for dogs on the market as well as some natural remedies for diarrhea; we ranked them according to efficacy, palatability and expense.

How to Choose the Best Probiotic Supplement for Your Dog

When selecting probiotics for your canine companion, keep the following criteria in mind:

  • Species and Strain: The list of ingredients should indicate the specific bacterial species and strain, such as Lactobacillus acidophilus.
  • Guaranteed CFU: The label should guarantee the number of colony-forming units (CFU) in millions or billions per gram. CFU is an estimate of viable bacterial or fungal numbers that the manufacturer guarantees will exist in their product.
  • Customer Service Contact: The product packaging or manufacturer’s website should have a customer service number so you can contact them with any questions.
  • Expiration Date and Storage Recommendations: The product should have a "best before" or expiration date. Storage time and conditions (i.e., excessive heat or cold) can reduce the viability of some bacterial strains. It is best practice to store your probiotics in a refrigerator.
Probiotics are easy to dispense and offer dogs, pets, and humans alike many health benefits and relief from chronic illness.

Probiotics are easy to dispense and offer dogs, pets, and humans alike many health benefits and relief from chronic illness.

1. Purina FortiFlora: The #1 Selling Dog Probiotic

Frequently recommended and sold by veterinarians, Purina FortiFlora Canine Nutritional Supplement is the number one selling probiotic for canines and our number one recommendation for dogs who suffer from occasional digestive issues such as loose stool and diarrhea. This supplement can safely be used on pregnant and lactating bitches as well as young puppies.

Reviews indicate that dog owners have observed high palatability for picky eaters and firm stools. This product regularly resolves IBS symptoms, sensitive stomach issues, and chronic soft stool. Whelping bitches that are deficient in iron or may have overindulged in nutrient-rich placenta will benefit from this probiotic. Why? Probiotics aid in both the absorption of iron and the reversal of iron-toxicity damage in the gut, according to one such study on mice by the College of Food Science and Engineering.

Fast-acting, Fortiflora has no apparent "build up" time and is efficacious from the first sprinkling on the dog’s food. We give this product an “A” for correcting loose stools.

Ingredients: Animal digest, Enterococcus faecium, L-ascorbyl-2-polyphosphate (source of vitamin C), vitamin E supplement, zinc proteinate, beta-carotene, salt, manganese proteinate, ferrous sulfate, copper proteinate, calcium iodate, sodium selenite.

When dispensed by veterinarians, this can be an expensive product. However, if purchased online through Amazon and other retailers, the sachets (foil packages of powdered product) cost approximately $0.93 per piece ($27.99 per 30-sachet package). This can still be an expensive daily addition if you have more than one dog needing a probiotic on a daily basis. Also, this product does not contain many strains of bacteria; if you are seeking to curb food allergies or skin conditions, you should try the VetriScience probiotic first. We recommend this product as a quick fix for diarrhea, but not as a product to improve gut health and the immune system on an ongoing basis.

The #1 Selling Dog Probiotic

The #1 Selling Dog Probiotic

2. Pet Ultimates: The #1 Selling Probiotic for Canine Allergies, Skin and Ear Infections

While Pet Ultimates Probiotics for Dogs scores well for firming up stool, it gets its highest marks for resolving chronic skin allergies and infections. From itchy skin and excessive licking to hair loss and staph infections, this product has helped clear up skin issues, promote hair regrowth, and diminish tear stains.

Pet Ultimates guarantees 22 strains of probiotics in their flavorless powder supplement, which is made in the USA. They offer great customer service and back up their product with a 100% refundable guarantee—you even get to keep the product if you are not 100% satisfied with the results, so no need to ship it back. This is a company whose customer service is highly responsive to negative reviews. If you express any issues with clumping or palatability, they will quickly offer you a replacement.

Pet Ultimates comes with a quarter teaspoon scoop and approximately a 60-day supply. For large dogs, that is a dollar a day at $35.95 per container, making this one of the more expensive supplements. We give this product an "A." Their product falls slightly below perfect due to the high cost for large dogs but good value for small and medium-sized breeds.

Note: This commercial dog probiotic contains 22 species of probiotics at 2 billion CFUs. Still, this is half of what kefir milk offers in probiotics; however it is easy to administer with your dog's current feeding regimen and requires none of the maintenance that culturing kefir does.

Pet Ultimates Dosing

Based on below product at 137 grams per container; administer once a day.

SizeServing AmountScoops

Dogs 50 lbs and under

1/4 tsp

1 scoop

Dogs 50 lbs and over

1/2 tsp or 2 (1/4 tsp)

2 scoops

3. VetriScience Laboratories: The #2 Selling Dog Probiotic

VetriScience Laboratories Probiotic Everyday Dogs Bite-Sized Soft Chews is our number one recommendation for dogs requiring a daily probiotic as a part of their overall health regimen. Very cost-effective, it averages $10.99 for 60 chews on Amazon making it the best value. The VetriScience probiotic chews alleviate gas, loose stool, bad breath, tear staining (according to Pet WebMD), and yeast infections seen in the ears and skin. In fact, alleviating symptoms of extreme gas is this product's greatest achievement, and owners are duly gratified. Given the many conditions this probiotic has helped with, we give it an “A+” for all-around efficacy and value.

Ingredients: This chew contains 9 strains of bacteria at 286 million CFU/gram, including Bacillus subtilis, Bacillus coagulans, Lactobacillus acidophilus, Bifidobacterium thermophilum, Bifidobacterium longum, Lactobacillus fermentum, Lactobacillus casei, Bifidobacterium bifidum, and Enterococcus faecium.

Given as treats, these chews are highly palatable and most dogs look forward to receiving them. When paired with limited ingredient diets, this probiotic demonstrates excellent results. Old dogs with acute skin conditions and yeast infections respond exceedingly well. If you feed your dog a raw diet, these chews are the best solution for the delivery of a commercial probiotic product, as powders are difficult to administer on raw chicken quarters, etc. For dogs that do not find these chews tempting, powder and capsule forms are also available.

VetriScience Dosing

Based on VetriScience Laboratories Probiotic Everyday Dogs Digestive Health Supplement 60 Bite-Sized Soft Chews; to be adminsitered once a day.

SizeServing AmountCount

Small dogs (30 lbs and under)

3 grams

1 chew

Medium dogs (30-60 lbs)

6 grams

2 chews

Large dogs (60 lbs and over)

9 grams

3 chews

4. Dr. Mercola: The #3 Selling Probiotic for Pets

Dr. Mercola Complete Probiotics for Pets 90-Gram Powder can be safely used on both cats and dogs. In a multi-pet household with both cats and dogs, this product will not create any digestive issues for pets that crossover to their housemates' bowls. However, because of the large amount required per serving for larger dogs, this is not a cost-effective solution, although smaller dogs and cats benefit at a reasonable price.

Ingredients: Lactobacillus Acidophilus, Lactobacillus Casei, Lactobacillus Plantarum, Streptococcus Thermophilus, Saccharomyces Boulardii, Enterococcus Faecium, Lactobacillus Rhamnosus, Lactobacillus Bulgaricus, Bifidobacterium Lactis, Bifidobacterium Longum, Bifidobacterium Bifidum, Bifidobacterium Breve, Bifidobacterium Animalis and Lactobacillus Sporogenes (14 strains of bacteria). 38 billion CFU per scoop; acid and bile resistant.

Cat owners saw a substantial reduction in vomiting which is commonly seen in older cats. Dog owners saw a reduction in gas and bloating as well as a reduction in loose stool. Many owners were disappointed with the small quantity of product relative to the large container’s size. While this product does work well for smaller animal owners, we give it a “B” for value at $1.30 per serving for medium to large dogs.

Dr. Mercola Dosing

Per 1 scoop; 2-gram scoop included in 90-gram product. To be administered once a day.

Species and SizeServing AmountScoop(s)

Cats (2+ lbs.)

1 g

1/2 scoop

Toy Breed Dogs (up to 14 lbs.)

2 g

1 scoop

Small Breed Dogs (15-29 lbs.)

3 g

11/2 scoop

Medium Breed Dogs (30-49 lbs.)

4 g

2 scoops

Large Breed Dogs (50-79 lbs.)

5 g

21/2 scoops

Giant Breed Dogs (80+ lbs.)

6 g

3 scoops

5. Probiotic Miracle: The #4 Selling Pet Probiotic Disappoints

Probiotic Miracle markets itself as the number one selling canine probiotic. Our research indicates it is more likely the number four selling product on the market and well behind Purina, Pet Ultimate, and VetriScience products. Consumers of this probiotic tout it for clearing up eye, skin, and yeast conditions in addition to joint inflammation issues. A majority of users gave this product high ratings, although a small percentage reported a reduction in gas but ineffectiveness for other symptoms. Given that a small percentage of users had poor or mixed reviews, we would give it a “C+," however, the money-back guarantee (discussed below) bumps this product up to a “B-."

Ingredients: 2 billion CFU per serving, six strains of bacteria: L. acidophilus, B. animalis, L. rhamnosus, L. salivarius, L. fermentum, L. reuteri. Also contains pre-biotics. 100% natural, vegetarian, no gluten, no dairy, no soy, no fillers, no flavorings.

Probiotic Miracle does offer a 100% money-back guarantee, with guaranteed results against diarrhea, loose stool, and yeast overgrowth. However, this product requires time to build up in the system and the guarantee expires 60 days from product shipment.

People with multiple dogs with gluten allergies and issues with loose stool and yeast-related problems may want to try this product before trying one of the more expensive ones. Keep an eye on the calendar if you want to take advantage of the money-back guarantee.

Probiotic Miracle Dosing

Based on the below product at 120 scoops per container; may dose up to twice per day. Read label for instructions.

SizeServing AmountScoop (s)

50 lbs. and under

363 mg

1 scoop

50 lbs. and over

726 mg

2 scoop

Kefir Grains for Inexpensive, Natural Probiotics for Dogs

They look like cauliflower and produce a probiotic-rich milk that is great for people and dogs.

They look like cauliflower and produce a probiotic-rich milk that is great for people and dogs.

6. Natural Probiotics: Kefir and Greek Yogurt for Dogs

Following a round of antibiotics, dog owners have long used a tablespoon of low-fat yogurt to readjust the bacteria in their dog’s intestines. Kefir, a super cousin of yogurt, is easy to make and packed with additional benefits; it is a low-cost and safe daily addition to your dog or puppy’s diet.

While similar in taste, Greek yogurt and Kefir have different bacterial qualities. Yogurt's bacteria is transient, meaning it temporarily adjusts the gut flora with one or two strains of bacteria. Kefir on the other hand actually colonizes the gut with between 30-50 strains of bacteria. If you purchase kefir grains and make your own, it is much less expensive than pricey Greek yogurt.

Why Is Kefir so Beneficial?

Kefir contains minerals and essential amino acids that help the body with its natural healing processes, including tryptophan, which is among these essential amino acids. Tryptophan is well-known for its relaxing effect on the nervous system and may help calm high-drive or highly anxious dogs.

Kefir offers many health benefits and contains calcium and magnesium, both of which are critical for healthy nervous system function, so supplementation can have a particularly calming effect on the nerves. It is also rich in vitamins B12, B1, and vitamin K, promoting healthy-looking skin, boosting energy, and promoting longevity. It is high in probiotics and excellent at rebalancing intestinal bacteria, boosting immunity, and correcting loose stool and diarrhea. Dogs who have suffered from Lyme disease have seen boosts in overall health and energy when kefir is added to their diet.

We recommend kefir as the best probiotic you can give your dog, garnering it an "A+" on the efficacy and value. If you have multiple dogs, regenerative kefir is the most affordable solution. It's natural, it works and it is easy to make. However, if you don't have the time to invest or find that making your own milk kefir is unappealing, we recommend the VetriScience probiotic supplement for the all-around health benefits it provides.

How to Make Kefir

Canine Health Issues Survey

Further Reading

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

© 2013 Barbara Fitzgerald


Dawn Caron on May 31, 2019:

I am a nurse and raise German Shepherds and have come to understand and produce Kefir that I use for myself and my dogs (and puppies) daily. The article was great, but after seeing many videos on working with Kefir I found the one in the article to be the worst possible choice for encouraging and helping people understand Kefir. I can not fathom why you chose this one.

Danni California on May 24, 2019:

I will never use anything that has enterococcus faecium as an added ingredient due to a rare gram positive strain infection I contracted after a surgery. I was hospitalised for two weeks because this bacateria is antibiotic resistant. The only antibiotic left to try was not covered by my health insurance and for 1 week worth of this medication was 5 grand... Be very careful when using something like this if you're using a probiotic for your pet with e faecium as one of the ingredients. Those with weakened immune systum or open wounds should absolutely AVOID this! Probiotic Miracle has worked wonders for my dog and does'nt contain animal digest which is the scrapings of non decomposing animal flesh... Be careful!

Enterococcus faecium is a Gram-positive, alpha-hemolytic or non-hemolytic bacterium in the genus Enterococcus.[1] It can be commensal (innocuous, coexisting organism) in the gastrointestinal tract of humans and animals,[2] but it may also be pathogenic, causing diseases such as neonatal meningitis or endocarditis.

Danni on May 24, 2019:

I will never use anything that has enterococcus faecium as an added ingredient due to a rare gram strain infection I contracted after a surgery. I was hospitalised for two weeks because this bacateria is antibiotic resistant. The only antibiotic left to try was not covered by my health insurance and for 1 week worth of this medication was 5 grand... Be very careful when using something like this if you're using a probiotic for your pet with e faecium as one of the ingredients. Those with weakened immune systum or open wounds should absolutely AVOID this! Probiotic Miracle has worked wonders for my dog and does'nt contain animal digest which is the scrapings of non decomposing animal flesh... Be careful!

Tammie on September 23, 2017:

What's good for bloating?

Lady Marianne Cottee on September 08, 2017:


I give Kefir to my two HuskyXMals. Approx 2 tblspns daily.

I understand it's not necessary daily but they love it. And no health isdues in their 5+ years.

Following a panic gastritis episode with them after devouring a year old plus xmas fruit cake almost whole, with icing and marzipan .. from the food waste bin that WAS up high and away - I gave them 200ml of Kefir each.

Both had thrown up and one did So again. (My Vet said this was a good thing). The diarrhoea was much and awgul.

My vet was fast - they were in, on IV's & obs - predicted 3-5 days. They were home in 36 hours under my watch (retired nurse) as they recovered very fast.

I am sure my actions helped although their extreme good health and larger 'body mass' contributed too.

They're between 40 & 42kg... however are now on a diet as this has crept up during (less) much hotter/humid summer activity.

So many benefits around Kefir.

A UK Radio Times article Apr/May this year spoke of a woman using this as a last resort on her husband, given up as a terminal case with MRSA.

She has increased now from one to four goats and makes her own Kefir to sell.

She saved him.

Barbara Fitzgerald (author) from Georgia on June 03, 2017:

Thanks for your comment Cheryl. Animal digest is a common ingredient used in many pet foods. It is produced by the chemical or enzymatic hydrolysis of clean animal tissue that has not undergone decomposition. These animal tissues do not include hair, horns, teeth, hooves, and feathers, with the exclusion of trace amounts that are unavoidable even after acceptable processing methods.

According to the US Food and Drug Administration, a digest is an additive that has been treated with heat, enzymes, or also acids to produce a concentrated product intended as a natural flavoring. So this is what makes the Forti Flora palatable to dogs.

Cheryl on June 03, 2017:

Forth flora contains animal digest, I'm not sure what that is exactly but it does not sound good

Barbara Fitzgerald (author) from Georgia on January 03, 2017:

Hi marie: Thanks for visiting and catching that. You are correct Vetri-Science was the recommended product.

For the kefir, you can get a mason jar and put one kefir grain (two if they are small) in the jar and fill with 2% lowfat milk. In the course of two days it will begin to thicken to a runny yogurt consistency. It will keep getting thicker, so you will want to use it quickly, within days two-four. Give your dog a half cup a day. You can add it to a smoothy or granola for your own health benefits. Once you have used it up, rinse the Kefir grains and mason jar, return the kefir grains to the jar and refill with milk. You can use them seemingly for forever.

Marie on January 02, 2017:

Thank you for writing this article.

The article seemed helpful, but I watched the video and it didn't teach me anything--he basically strained the kefir and talked about what a mess it was, and that was it. I didn't get how to get the kefir to strain in the first place. Is it just milk? What kind of milk? I guess I will just buy the kefir...

And at the end of your article, you say that you recommend Nutri-Science probiotic for the all around health benefits, but the Nutri-Science brand isn't even mentioned on your list. Do you mean the Verti-Science probiotic? Because you only have that brand or Purina, Mercola, and Probiotic Miracle brands--no Nutri-Science brand.

Lastly, do you have any recommendations for how often or how much kefir or greek yogurt to give your dog on a regular basis for general GI health?

Thank you!

Barbara Fitzgerald (author) from Georgia on August 14, 2016:

Hi Norma: Yes, you can buy it instead of making it yourself. It is not available to by in some areas. Greek yogurt with the enzymes still alive can work too.

Norma Estep on August 14, 2016:

can i buy kefir instead of make it? Theyy sell it at the store its next to the yogart

usillyrabbitu on July 16, 2016:

Unfortunately the vetri science does not contain Enterococcus faecium. I don't know if it used to, but it now has Enterococcus thermophilus instead, which I understand is not the same.

Mike Harper @Best Probiotics for Dogs on June 08, 2016:

We, humans, ingest probiotics to protect our gut. But our pets can also benefit from probiotics, especially dogs. Why there are probiotics for dogs, you may ask? To help improve the health of your beloved pooches, of course!

Barbara Fitzgerald (author) from Georgia on November 12, 2015:

Hi Joy: That definitely works for a lot of dogs and cats. Gluten can cause many digestive issues, especially when they are the number one ingredient. Purina Forte Flora is great for the occasional stomach upset, and some dogs will need a prolonged regimen of probiotics to help get their gut straight even after glutens have been removed from the diet. Thanks for the comment.

Joy Giffard on November 12, 2015:

I find the best way of dealing with doggy allergies is to completely eliminate gluten from their diet.

Craig on May 30, 2014:

Hey Solaras, you mention the importance of looking for the probiotic strain above, but you never listed one with Lactobacillus acidophilus. The strain would actually come after that (Genus) (Species) (Strain).

Barbara Fitzgerald (author) from Georgia on January 13, 2014:

Hi Jennifer: Thanks for your comment. We gave it an A+ because it did help with a wide variety of allergy conditions, including tear staining and bad breath in addition to gas and diarrhea , as well as its relative low cost.

Barbara Fitzgerald (author) from Georgia on July 31, 2013:

Thanks trusouldj, unfortunately some friends and I have several cats and dogs with mild to severe food allergies that have made this research necessary. I think I will do a review of the best cat food grain free gluten free products next, as I have a cat that has been tested to be allergic to all carbohydrates... Happily we have found some good solutions that finicky cats will eat!

LaZeric Freeman from Hammond on July 31, 2013:

Your knowledge is amazing. Keep up the good work.

Barbara Fitzgerald (author) from Georgia on July 08, 2013:

Hi epbooks. I would save the Fortiflora for loose stools or food changes, unless it is getting ready to expire. I think that is its best use. If you are wanting to boost immunity, then look at the Vetriscience or into the Kefir. You can take the kefir too and put it into smoothies!

Elizabeth Parker from Las Vegas, NV on July 07, 2013:

Very useful! We have foriflora in the house but haven't given it to our dogs in a while. It may be something that I will look into. Thanks for posting!