Guide

Is there a generic Culturelle? And a generic Florastor?

Culturelle and Florastor are the two single-strain probiotics a pharmacist is most likely to name, and both cost more than the shelf around them. The question people search for is whether there is a generic Culturelle or a generic Florastor: a cheaper bottle with the same words on the front that is the same thing. The answer depends on one line of small print — the strain — and it is different for the two products.

What “generic” means for a probiotic

A generic drug has the same molecule as the brand. A probiotic has no molecule; it has an organism, and organisms come in strains. Lactobacillus rhamnosus is a species; L. rhamnosus GG is one strain of it, isolated from one human sample in 1985 and documented in more than a thousand studies since. A different L. rhamnosus strain is a different product with its own, usually much thinner, evidence, in the same way that two people with the same surname are not the same person.

So the two lines to read on any bottle are the strain designation (the letters or number after the species name) and the CFU figure, together with whether that figure is guaranteed through the best-by date or only at manufacture. The rest of the front of the pack does not change what the product does.

Generic Culturelle: the other LGG products

Culturelle’s strain is L. rhamnosus GG at 10 billion CFU per capsule (12 billion in the Pro Strength version). Unlike Florastor’s yeast, LGG is not exclusive to one finished product: the strain belongs to Chr. Hansen, now part of Novonesis, which sells it as an ingredient and licenses the LGG mark to brands that use it. That is why a genuine equivalent exists.

PureGG’s other ingredients are the capsule itself (cellulose and water), so it is the closest thing to Culturelle in a different bottle, at a higher dose for about the same daily cost. Whether 25 billion is worth more than 10 billion is a separate question: for the outcomes where LGG has an evidence-based dose, 10 billion a day is already at or above it (see how many CFU do you need?).

The store-brand capsules shelved beside Culturelle are a different matter. In the online listings we read, products sold as “compare to Culturelle” do not consistently name GG; several give L. rhamnosus or a multi-strain blend and stop there. Treat a panel without the letters GG as a different strain, because it is one.

Generic Florastor: the cheaper S. boulardii capsules

Florastor’s strain is S. boulardii CNCM I-745, 250 mg per capsule, a live yeast rather than a bacterium. Its case rests on a meta-analysis of 21 randomized trials in 4,780 people in which the yeast cut the risk of antibiotic-associated diarrhea, and on the fact that, being a yeast, it is not killed by the antibiotic it is taken alongside. The manufacturer’s position is that there is no substitute, and on the trial record that is true: the studies were run on I-745.

Other brands sell S. boulardii from their own strains — CNCM I-1079, CNCM I-3799 and DBVPG 6763 are the ones named in the research literature — or list the species without a strain at all. What is known about how much that matters comes from a 2026 study in iScience that sequenced and tested five commercial S. boulardii isolates against three ordinary baker’s-yeast strains. The S. boulardii isolates shared a chromosomal inversion and other lineage-specific features, and all five showed the same probiotic-relevant behavior: acid tolerance, elevated acetate and succinate production, suppression of inflammatory signaling in gut cells. The authors describe the lineage as “functionally coherent.” That is the strongest available argument that a generic S. boulardii is doing the same kind of thing. It is a laboratory argument, and it is not a trial.

“None named” means the online listing we read gives the species and the CFU and no strain designation. If the bottle in your hand names one, that is more than the listing offers. NOW’s panel prints its strain as Saccharomyces cerevisiae var. boulardii I-3799. Across the probiotics in the catalog, the share of labels that name a strain is counted on its own page.

What to check before you switch

• The strain designation. CNCM I-745 for Florastor; the letters GG for Culturelle. A species name on its own is not a match.
• CFU “through expiry,” not “at manufacture.” The two can differ by orders of magnitude, and only the first tells you what is in the capsule when you take it.
• Storage. Both Florastor and Culturelle are shelf-stable; some cheaper capsules are not, and a refrigerated product that has spent a week in a delivery van is not the product on the label.
• The price per day, not per bottle. The table figures above are per capsule at the listed dose.

Products in this catalog

Common questions

Sources

• Florastor. “The One Probiotic Strain You Need: Saccharomyces boulardii CNCM I-745.” florastor.com
• Florastor Healthcare Professionals. “There is no substitute for Florastor.” florastorhcp.com
• Duffey HE, Hedin KA, Gelli HP, Vaaben TH, Sommer MOA. “Genomic and phenotypic comparisons reveal lineage-specific traits of the probiotic Saccharomyces boulardii.” iScience, 2026;29(5):115706. pubmed.ncbi.nlm.nih.gov/42095083
• NOW Saccharomyces Boulardii, 5 billion CFU, 60 capsules: price and rating. amazon.com/dp/B0053W995W; 120 capsules: amazon.com/dp/B07YBKYPSX
• Jarrow Saccharomyces Boulardii + MOS, 5 billion CFU, 90 capsules: price and rating. amazon.com/dp/B0013OVW0E
• Klaire Labs SFI Health Saccharomyces Boulardii, 3 billion CFU, 120 capsules: price. amazon.com/dp/B003PQHBCQ
• Chr. Hansen / The Probiotics Institute. “Lactobacillus rhamnosus, LGG.” theprobioticsinstitute.com
• Pure Encapsulations PureGG 25B, 60 capsules: label, price and rating. amazon.com/dp/B07WJXVQJ5
• National Institutes of Health, Office of Dietary Supplements. “Probiotics — Health Professional Fact Sheet.” ods.od.nih.gov