FortiFlora vs Proviable for Dogs: Strains, CFU, Evidence

FortiFlora and Proviable are both dog probiotics, built differently. FortiFlora is a single strain, Enterococcus faecium SF68, in a flavored powder sachet. Proviable-DC is seven strains plus prebiotics in a capsule, and the Proviable Kit adds a kaolin-pectin paste for short-term loose stool. SF68 has more published dog trials. Neither replaces a vet visit for an unwell dog.

For what probiotics in general can and can’t do for sudden diarrhea, see Do Probiotics Help Acute Diarrhea in Dogs?.

This page is general information. It is not veterinary advice.

When to call the vet first. Puppies with diarrhea. Blood in the stool, or black stool. Vomiting as well as diarrhea. Lethargy or not eating. Diarrhea that lasts more than 48 hours, or keeps coming back. A dog that may have eaten a toxin or a foreign object. Dogs with other illnesses or on other medicines.

FortiFlora vs Proviable at a glance

We checked the Proviable manufacturer pages and Purina’s FortiFlora tablet page in October 2026. Other details reflect retailer listings as of publication. Formulas change, so check the package. Figures are label minimums for US products. Prices are not shown.

Product (ASIN)	Form	Strain(s)	CFU per serving (label minimum)	Prebiotic?	Other notable ingredients	Label directions	Labelled for	Dog evidence for this product or strain	Site evidence status	Amazon
FortiFlora dog powder, 30 sachets (B001650NNW)	Powder sachet	E. faecium SF68 (Purina now also uses the name Enterococcus lactis SF68)	US label: 1 × 10⁸ CFU/g. Per-sachet amount: see label	No	Animal digest or “liver flavor” (flavoring), vitamins and minerals; listings differ on brewers dried yeast, so check the box	One packet daily or as directed by your vet	Dogs (separate cat formula)	SF68: mixed results in shelter dogs (Fenimore 2017; Bybee 2011)	MIXED	Check price on Amazon
FortiFlora chewable tablets, 45 ct (B083XLYRYH)	Chewable tablet	SF68 (Purina’s shop page names it Enterococcus lactis SF68)	1 × 10⁸ CFU per 1.77 g tablet on Purina’s shop page; another Purina label states 1 × 10⁸ CFU/g, so check the pack	No	Gum arabic, liver flavor, cellulose	One tablet daily or as directed by your vet	Dogs	Same strain as the powder; we found no trial of the tablet form	MIXED	Check price on Amazon
FortiFlora chewable tablets, 90 ct (B083XD2V4C)	Chewable tablet	As 45 ct	As 45 ct	No	As 45 ct	One tablet daily	Dogs	As 45 ct	MIXED	Check price on Amazon
Proviable-DC capsules, 80 ct (B001O3UE9E)	Capsule (give whole or open and sprinkle)	7 strains (listed below)	5 billion CFU per capsule	Yes: FOS, gum arabic	Maltodextrin, gelatin capsule, titanium dioxide	1 capsule daily or as directed by your vet	Dogs and cats	No randomized dog trial of Proviable found; one open-label cat study (Hart 2012)	MIXED	Check price on Amazon
Proviable sprinkle capsules, 30 ct (B0050JM626)	Capsule	See label	See label	See label	See label	See label	See label	No trial of this product found	MIXED	Check price on Amazon
Proviable chewable tablets, 60 ct (B08BW6HPCM)	Chewable tablet	Same 7 strains as Proviable-DC (manufacturer page)	5 billion CFU per tablet (manufacturer page)	Yes (manufacturer page)	See label	See label	Dogs	No trial of this product found	MIXED	Check price on Amazon
Proviable Kit, dogs, 30 mL paste + 10 capsules (B001O490JI)	Kaolin-pectin paste + capsules	Same 7 strains	Paste 0.5 billion CFU per gram; capsule 5 billion CFU	Yes: FOS, gum arabic	Kaolin, pectin, soybean oil, dextrose, sucrose, artificial beef flavor	Paste: 21–50 lb 3–4 mL, over 50 lb 5 mL, 2–3 times daily for 48–72 h; then 1 capsule daily until finished	Dogs	No trial of this kit found	No kit trial; see note below	Check price on Amazon
Proviable Kit, small dog/cat 15 mL (B001O477W0)	As above	Same 7 strains	As above	Yes	As above	Paste: dogs 0–20 lb 1–2 mL, cats 1 mL, 2–3 times daily for 48–72 h (manufacturer page)	Small dogs and cats	No trial of this kit found	No kit trial; see note below	Check price on Amazon

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What’s in each product

FortiFlora powder

One strain, SF68. The US label gives 1 × 10⁸ CFU per gram. Check the box for the amount per sachet. The EU and UK product is labelled 5 × 10⁸ CFU/g. That is a different market, so we use the US figure here.

The powder also contains a flavoring, vitamin C, vitamin E, beta-carotene, trace minerals and salt. Purina says its “animal digest” comes from hydrolyzed pork liver and poultry and was renamed “liver flavor” in 2020. Sources differ on whether the powder contains brewers dried yeast, so check the ingredient list on the box if that matters for your dog.

FortiFlora chewable tablets

Same strain in a liver-flavored tablet with cellulose and gum arabic. Purina’s shop page now names the strain Enterococcus lactis SF68, while older labels and studies call it Enterococcus faecium SF68. It is the same SF68 strain under a newer name.

Purina sources differ on the count. The shop page lists 1 × 10⁸ CFU per 1.77 g tablet, while a Purina label PDF reads 1 × 10⁸ CFU/g. Check the figure printed on your pack.

Proviable-DC capsules

Seven strains, a minimum of 5 billion CFU per capsule:

Enterococcus faecium NCIMB 30183
Bifidobacterium bifidum NCIMB 30179
Streptococcus thermophilus NCIMB 30189
Lactobacillus NCIMB 30184 (the manufacturer’s page lists L. helveticus; some retail listings and the 2012 cat study say L. acidophilus; check the current package)
Lactobacillus delbrueckii (bulgaricus) NCIMB 30186
Lactobacillus casei NCIMB 30188
Lactobacillus plantarum NCIMB 30187

Because it pairs probiotics with prebiotics, Proviable is a synbiotic (see Synbiotics for Dogs: Do Probiotic + Prebiotic Combinations Matter?). The capsule contains prebiotics (FOS and gum arabic), maltodextrin and a gelatin shell. You can give it whole or open it over food. The label directions are 1 capsule daily for dogs and cats of all sizes, or as your vet directs.

Proviable Kit (diarrhea support kit)

The kit pairs an oral paste with 10 Proviable capsules. The paste contains kaolin and pectin plus the same probiotic strains at 0.5 billion CFU per gram. Kaolin and pectin are adsorbents (see Clay for Dogs With Diarrhea: Kaolin, Smectite and Bentonite Compared). They can firm stool, but they are not probiotics and they don’t treat the cause of the diarrhea.

The dog kit (30 mL) label gives 3 to 4 mL for dogs of 21 to 50 lb and 5 mL for dogs over 50 lb, two to three times a day for 48 to 72 hours. Then give 1 capsule a day until the capsules are finished. The label says to contact your vet if your dog does not improve within 48 to 72 hours. A smaller 15 mL size is sold for small dogs and cats. The manufacturer page gives 1 to 2 mL of paste for dogs up to 20 lb and 1 mL for cats, two to three times a day.

Proviable-Forte

You may see “Proviable-Forte” in search results. It is a higher-count version. The manufacturer’s Forte chewable tablet page lists 10 billion CFU per tablet and the same seven strains. It is not in our table, so we don’t link to it.

Does CFU matter?

More CFU or more strains does not automatically mean a better product. Probiotic evidence is tied to the exact strain and the condition studied. A large number on the label tells you how many bacteria the maker guarantees. It doesn’t tell you whether those bacteria help a dog with diarrhea. Our guide How to Read a Probiotic Label for Dogs: Strain, CFU and Formula Context covers what to look for. Our article Dog Probiotics for Itchy Skin: What Studies Show explains the same point for skin.

What the dog studies tested

E. faecium SF68 (FortiFlora)

Shelter dogs on metronidazole (Fenimore 2017). All dogs got metronidazole and a standard diet, plus either FortiFlora or a placebo (the same product without the probiotic) for 7 days. Normal stool by day 7: 68.8% with FortiFlora vs 37.5% without, which was not statistically significant (P = .1556). The share of days with normal stool was higher with FortiFlora, 65.6% vs 46.9% (P = .0496). It was a small shelter study.
Shelter cats and dogs (Bybee 2011). In 182 dogs and 217 cats, fewer cats given SF68 had diarrhea lasting 2 days or more (7.4% vs 20.7%). There was no detectable difference in dogs.
Giardia (Simpson 2009). In a crossover study of 20 adult dogs with chronic giardiasis but no clinical signs, 6 weeks of SF68 made no difference to Giardia cyst or antigen shedding, or to the immune measures tested, compared with placebo.
Puppies (Benyacoub 2003). This study measured immune markers in young dogs. It did not test diarrhea.

Two small studies in healthy dogs looked at lab values. After 14 days of SF68, mean vitamin B12 (cobalamin) fell, with moderately low levels in 8 of 18 dogs by day 28 (Lucena 2018). In another, liver enzymes did not change, but triglycerides rose and one dog developed high triglycerides (Lucena 2019).

Proviable strains

We found no randomized dog trial of Proviable itself (PubMed checked on October 15, 2026). The only published clinical study is an open-label trial of Proviable-DC in cats with chronic diarrhea, with no control group. In the 53 cats that finished 21 days, the average stool score went from 6.0 to 4.4, meaning firmer stool. Nutramax supplied the product (Hart 2012). The manufacturer cites university studies on fecal lactic-acid bacteria in dogs and cats. We could not find these on PubMed, so we report them only as the manufacturer’s claim.

Kaolin-pectin pastes: a different product was tested

A randomized trial in 148 dogs with acute diarrhea found faster resolution with a probiotic paste (median 32 vs 47 hours). That trial tested Pro-Kolin Advanced, a different product with a different strain (E. faecium 4b1707), and was funded by its manufacturer, ADM Protexin (Nixon 2019). It is not evidence for the Proviable Kit. We mention it only because search results sometimes link the two. What is known about clay and kaolin products in general is covered in Clay for Dogs With Diarrhea: Kaolin, Smectite and Bentonite Compared.

That trial did not test Proviable, and we found no published trial of the Proviable Kit.

The bigger picture

A 2019 systematic review of probiotics in dogs (Jensen and Bjørnvad) concluded that the data point to a very limited and possibly clinically unimportant effect on acute gastrointestinal disease. A 2024 meta-analysis for the ENOVAT guidelines (Scahill et al.) found that prebiotics, probiotics and synbiotics did not shorten acute diarrhea by a clinically significant amount, and that antibiotics had no clinically relevant effect in mild or moderate cases. No adverse effects were reported in the studies it included. The ENOVAT guidelines built on that review give recommendations on antibiotic and probiotic use (Jessen et al., 2024). Probiotics are often used as supportive care, but the evidence behind them is weak. Whether your dog needs antibiotics is your vet’s decision. More detail is in Do Probiotics Help Acute Diarrhea in Dogs?.

When to choose which

There is no head-to-head trial, so we can’t name a winner. These are label-based pointers:

Your vet named one. Use that one, at the label amount or the amount your vet gave.
You want the strain with the most published dog studies. That is FortiFlora (SF68). The results in dogs are mixed.
Your dog won’t eat a flavored powder, or you want to avoid animal digest. Proviable-DC capsules can be opened over food. Check that gelatin and the other ingredients suit your dog.
Short-term loose stool in a dog that is otherwise bright and eating. The Proviable Kit’s paste may firm stool, but kaolin does not treat the cause. Stick to the label’s 48 to 72 hours, then call your vet if there’s no improvement.
Your dog is on a hydrolyzed or elimination diet for food allergy. Ask your vet first. Purina says FortiFlora’s flavoring is made from hydrolyzed pork liver and poultry. The label does not claim the product is hypoallergenic, and an added animal-protein flavor could matter during a diet trial.
Giving both together. No study has tested FortiFlora and Proviable together, and no benefit has been shown. Ask your vet.

A note on cats

Purina sells a separate FortiFlora product for cats with its own ingredient list, so check the cat label. Don’t apply dog findings to cats or cat findings to dogs. In the shelter study, fewer cats given SF68 had diarrhea for 2 days or more (Bybee 2011).

Proviable-DC capsules are labelled for dogs and cats. Its only published clinical study is the open-label cat trial (Hart 2012). The Proviable Kit comes in a 15 mL small dog/cat size and a 30 mL dog size.

Claims we avoid

That either product cures, treats or stops diarrhea.
That more CFU or more strains means a stronger product.
That a probiotic replaces antibiotics or a vet visit.
That trials of other products (Pro-Kolin, Visbiome or other multi-strain probiotics) are Proviable evidence.
That FortiFlora is hypoallergenic or safe for food-allergic dogs.
Puppy-safety claims beyond what the label says.
Anything about price or value.
Cat claims drawn from dog studies, or the other way round.

When to call the vet instead

Call your vet rather than relying on a supplement if:

your dog is a puppy;
there is blood in the stool, or the stool is black;
your dog is vomiting as well;
your dog is lethargic or not eating;
the diarrhea lasts more than 48 hours, or keeps returning;
your dog may have eaten a toxin or a foreign object;
your dog has other illnesses or takes other medicines.

Diarrhea that keeps coming back over weeks is a different problem from a short bout. For one long-term option your vet may discuss, see Psyllium for Dogs With Chronic Large-Bowel Diarrhea: What Does the Evidence Show?.

Where to check the labels

Label details reflect manufacturer listings as of publication. Formulas change, so check the package.

FortiFlora powder: Amazon listing B001650NNW; US label text at canpharm.com/products/fortiflora.
FortiFlora chewable tablets: shop.purina.com/fortiflora-dog-chewable-tablet (checked October 15, 2026).
Proviable-DC capsules: proviable.com/proviable-dc-capsules-for-dogs (checked October 15, 2026).
Proviable chewable tablets: proviable.com/proviable-chewable-tablets.
Proviable Kit: proviable.com/proviable-kits-for-dogs (checked October 15, 2026).
Proviable-Forte chewable tablets: proviable.com/proviable-forte-chewable-tablets.

The full list of digestive products we track is in the Dog Digestive comparison. See also digestive best sellers vs evidence.

Dog Supplement Facts evidence status

MIXED for FortiFlora (SF68) and for Proviable-DC capsules and tablets. For the Proviable Kit we found no trial of the kit itself; the one randomized trial of a probiotic and clay paste tested a different product (Pro-Kolin Advanced). Ratings describe the ingredient or strain evidence. They don’t mean the exact product was tested.

Disclosures

Not veterinary advice. This page summarizes published research and product labels. Ask your vet before giving a supplement to a dog with diarrhea.
Links: Amazon links are not affiliate links. We earn nothing when you click them. No brand paid for placement.
Label data: label details reflect manufacturer and retailer listings as of publication. Formulas change, so check the package.

Check your dog's body condition score Not sure this is the right topic? Use the symptom checker

In our comparison: products that list probiotics only or synbiotics (probiotic + prebiotic) or clay / adsorbent anti-diarrhea formulas

97 of the 245 dog digestive products we compared list probiotics only or synbiotics (probiotic + prebiotic) or clay / adsorbent anti-diarrhea formulas (40%). 12 of them are among the 20 most popular products, and their median popularity rank is #79 of 209 ranked products. Our ingredient-level evidence rating for probiotics only or synbiotics (probiotic + prebiotic) or clay / adsorbent anti-diarrhea formulas: mixed / insufficient.

Product-level ratings, which look at the whole formula: 89 mixed, 8 insufficient.

Frequently asked questions

Is FortiFlora or Proviable better for dog diarrhea?

Neither is proven better. No trial has compared them directly. FortiFlora's strain, SF68, has more dog studies, with mixed results. We found no randomized dog trial of Proviable itself. Choose based on what your vet advised, the form your dog will take and the ingredients, and call your vet if your dog is unwell.

Can I give my dog FortiFlora and Proviable together?

No study has tested giving them together, and no benefit from combining them has been shown. If you are thinking about it, ask your vet first. Your vet can tell you whether either product makes sense for your dog and how long to use it.

Can I give my dog FortiFlora every day, or twice a day?

The label says to feed one packet daily or as directed by your veterinarian. Don't give more than the label amount unless your vet tells you to. If your dog still has diarrhea after a few days, or seems unwell, call your vet.

What is the Proviable paste for?

The paste in the Proviable Kit contains kaolin and pectin, which can firm stool, plus probiotics. The label directions run for 48 to 72 hours. It is not a long-term product, and it does not treat the cause of the diarrhea. Call your vet if your dog has not improved within that time.

What do Proviable-DC and Proviable-Forte mean?

Proviable-DC is the widely sold capsule with 5 billion CFU per capsule. Proviable-Forte is a higher-count version; the manufacturer's Forte chewable tablet lists 10 billion CFU per tablet. The manufacturer lists the same seven strains for both. A higher CFU count does not by itself mean a better result.

Is FortiFlora hydrolyzed or hypoallergenic?

Purina says the flavoring in FortiFlora, listed as animal digest or liver flavor, is made from hydrolyzed pork liver and poultry. The label does not claim the product is hypoallergenic. If your dog is on a hydrolyzed or elimination diet for a food allergy, ask your vet before adding FortiFlora or any flavored supplement.

Are FortiFlora for cats and dogs the same?

No. Purina makes a separate FortiFlora product for cats with its own ingredient list. Use the product made for your pet's species, and don't assume a study in one species applies to the other. In one shelter study, SF68 reduced diarrhea in cats but showed no detectable difference in dogs.

Does FortiFlora have side effects?

The diarrhea trial abstracts we reviewed did not report side effects, and Purina says none are expected, though it advises against use in dogs with severely weakened immune systems. Two small studies in healthy dogs found lower vitamin B12 and higher triglycerides after 14 days of SF68. If your dog gets worse, stop it and call your vet.

Do I need a prescription for FortiFlora or Proviable?

No. Purina says no prescription is needed for its veterinary supplements, including FortiFlora, and Proviable is sold over the counter. Buying without a prescription doesn't mean you should skip the vet for a dog with diarrhea that is severe, bloody or lasting more than 48 hours.

References

Fenimore A, Martin L, Lappin MR. Evaluation of metronidazole with and without Enterococcus faecium SF68 in shelter dogs with diarrhea. Topics in Companion Animal Medicine. 2017;32(3):100–103. PMID 29291770. doi:10.1053/j.tcam.2017.11.001.
Bybee SN, Scorza AV, Lappin MR. Effect of the probiotic Enterococcus faecium SF68 on presence of diarrhea in cats and dogs housed in an animal shelter. Journal of Veterinary Internal Medicine. 2011;25(4):856–860. PMID 21689152. doi:10.1111/j.1939-1676.2011.0738.x.
Simpson KW, Rishniw M, Bellosa M, et al. Influence of Enterococcus faecium SF68 probiotic on giardiasis in dogs. Journal of Veterinary Internal Medicine. 2009;23(3):476–481. PMID 19298607. doi:10.1111/j.1939-1676.2009.0283.x.
Benyacoub J, et al. Supplementation of food with Enterococcus faecium (SF68) stimulates immune functions in young dogs. Journal of Nutrition. 2003;133(4):1158–1162. PMID 12672936. doi:10.1093/jn/133.4.1158.
Hart ML, Suchodolski JS, Steiner JM, Webb CB. Open-label trial of a multi-strain synbiotic in cats with chronic diarrhea. Journal of Feline Medicine and Surgery. 2012;14(4):240–245. PMID 22412160. doi:10.1177/1098612X11434386.
Nixon SL, Rose L, Muller AT. Efficacy of an orally administered anti-diarrheal probiotic paste (Pro-Kolin Advanced) in dogs with acute diarrhea. Journal of Veterinary Internal Medicine. 2019;33(3):1286–1294. PMID 30882953. doi:10.1111/jvim.15481. (Tested Pro-Kolin Advanced, not Proviable.)
Jensen AP, Bjørnvad CR. Clinical effect of probiotics in prevention or treatment of gastrointestinal disease in dogs: a systematic review. Journal of Veterinary Internal Medicine. 2019;33(5):1849–1864. PMID 31313372. doi:10.1111/jvim.15554.
Scahill K, Jessen LR, Prior C, et al. Efficacy of antimicrobial and nutraceutical treatment for canine acute diarrhoea: a systematic review and meta-analysis for European Network for Optimization of Antimicrobial Therapy (ENOVAT) guidelines. The Veterinary Journal. 2024;303:106054. PMID 38049062. doi:10.1016/j.tvjl.2023.106054.
Jessen LR, Werner M, Singleton D, et al. European Network for Optimization of Veterinary Antimicrobial Therapy (ENOVAT) guidelines for antimicrobial use in canine acute diarrhoea. The Veterinary Journal. 2024;307:106208. PMID 39074542. doi:10.1016/j.tvjl.2024.106208.
Lucena R, Olmedilla AB, Blanco B, Novales M, Ginel PJ. Effect of Enterococcus faecium SF68 on serum cobalamin and folate concentrations in healthy dogs. Journal of Small Animal Practice. 2018;59(7):438–443. PMID 29667183. doi:10.1111/jsap.12845.
Lucena R, Novales M, Blanco B, Hernández E, Ginel PJ. Effect of probiotic Enterococcus faecium SF68 on liver function in healthy dogs. Journal of Veterinary Internal Medicine. 2019;33(6):2628–2634. PMID 31578761. doi:10.1111/jvim.15625.