Illustration, not a product photo.
A probiotic yeast. Because it is a yeast, antibiotics do not kill it.
478 owner comments (177 with a clear rating) from r/SIBO, r/Microbiome, r/IBS, r/Constipation, r/Supplements, November 2025 to October 2026. Top 17% of the 36 rated supplements.
Value is not rated: the example products differ too much in dose to compare cost fairly. How we score.
Saccharomyces boulardii is rated about average among the supplements we track: 4.0/5. Of 177 rated owner comments, 136 were positive, 9 mixed and 32 negative; 15 mention an unwanted effect. People talk most about urgency & loose stools and bloating & gas.
Reddit comments are self-reported and unverified. They tell you what people noticed, not whether a supplement works or is safe for you.
Read why probiotic strains are not interchangeable. See what owners report about gut supplements for antibiotics. See what owners report about gut supplements for loose stools.
Supplements can interact with medicines. Talk to a doctor or pharmacist first, especially if you are pregnant, take prescription medicine, or have red-flag symptoms. See supplement safety and interactions.
| Context | Rated owner comments | Positive | Negative | Unwanted effects |
|---|---|---|---|---|
| SIBO | 87 | 65 | 16 | 5 |
| After antibiotics | 43 | 39 | 4 | 1 |
| IBS-D & loose stools | 32 | 28 | 4 | 1 |
| Bloating & gas | 26 | 24 | 1 | 1 |
| IBS-C & constipation | 21 | 16 | 3 | 1 |
| Pain & cramping | 16 | 13 | 3 | 0 |
4/5 Cost“I've tolerated taking Florastor 3x a day during antibiotics.”
4/5“Just added S Boulardii, which I previously tried and reacted to but now doing much better on it.”
4/5 Die-offSide effects“There are probiotics which are fairly safe even with SIBO, s boulardii is one of them, it helped me a lot when I first started it, drink lots of water with it as the yeast is thirsty and you don't want to get constipated (start low so you…”
1/5“Boulardii followed by a month of daily lentils solved 3 years of gut imbalance for me.”
1/5“boulardii and ispaghol and librax I'm sort of free to eat garlicy foods, sugar, dairy, and meat without suffering from a flair up.”
4/5“S Boulardii helped me after a nasty food poisoning round, kept things from going completely off the rails while my system rebuilt itself”
4/5 RegularityUrgency & loose stools“I used s.boulardii, which has a lot of high quality evidence showing effectiveness against blastocystis.”
4/5 Bloating & gas“Goli wasn’t great for me gas wise, I switched to florastore and my life changed and I hardly fart (just stay hydrated)”
4/5“Also look into florastor - it works very well for me.”
3/5“I had a very negative s boulardii interaction too and haven’t posted about it until now.”
5/5“I couldn’t do an intense protocol because I was breastfeeding, so I started taking Florastor and it’s been life changing.”
4/5 Bloating & gas“I take S Boulardii with IBSC! Less info / studies for it with IBSC but it definitely reduced my bloating. Hasn’t helped much with motility, but the bloating relief is so worth it.”
3/5“I have never had success in Vagal "fixing," have tried machines boulardii etc etc and it just doesn't seem to get any better.”
4/5 Pain & cramping“I’ve had ibs-D for decades, and in the last month I started using the Nerva app (hypnotherapy for IBS) and started taking Florastor.”
4/5 Urgency & loose stools“Saccharomyces boulardii and psyllium were the two things I tried at first, and they helped a lot with the urgency.”
4/5“What has helped in the meantime is when I start to flare a bit again despite my daily S Boulardii dose, I just fast about 8-12 hours to give the gut rest time and even that helps a lot.”
4/5“Florastor helped me get back on track after pancreatitis and gastritis.”
4/5“Since you ruled that out, I would get florastor probiotic and take that 30 days.”
4/5 Bloating & gas“Florastor mainly helped me with gas, ibs stuff.”
4/5 Regularity“I also have mcas and when I started s boulardii the foods I could eat were minimal.”
4/5“S Boulardii helped me a lotttt with brain fog.”
4/5 Bloating & gas“S Boulardii helps me greatly but I need to cycle it as my gut gets used to it and everything pretty quickly, same happened with milk kefir but I had such great results with kefir within a week and then nothing so I stopped..”
4/5“Also I take probiotics like Florastor once a day and it helps but I watch my diet a lot and keep a journal.”
5/5“Psyllium husk and florastor have made a huge difference for me.”
4/5“Specifically for me it was s.boulardii, which has a lot of evidence, but I also find kombucha works well too.”
4/5“boulardii and ant-parasite medication might be helping somewhat for me, but it's tough making progress.”
4/5 Urgency & loose stools“I was having the same issue and started taking Florastor probiotic suggested by my GI doctor and it helped within a few days.”
4/5“Boulardii, lactobacillus and bifido strains since stopping with antimicrobials and they’ve made a big difference for me personally.”
4/5“boulardii for the next time that I must take antibiotics.”
4/5“Something that has helped me notably after antibiotics is sacharomyces boulardii.”
4/5“Florastor helped me a lot when my gut felt completely thrown off.”
4/5 Urgency & loose stools“To be frank, I was experiencing a lot of diarrhea, and taking Florastor helped “solidify” things.”
2/5“Tho this SIBO I had was because of a probitoic (florastor) I tired to take to be healthy but that was a big mistake and backfired on my gut.”
5/5“Boulardii for exactly that reason, it’s been a lifesaver for me during flares since it doesn't colonize or feed the fire.”
4/5“I take a few select supplements, but I did do four Florastors daily.”
These are examples of Saccharomyces boulardii products sold on Amazon. They are not ranked by Reddit and the score above is for the ingredient, not a specific product. Check the label for dose and other ingredients.
Published studies (we list them so you can read the evidence yourself; inclusion is not an endorsement):
Across 478 Reddit comments from people who say they have used it, 136 of 177 rated comments were positive and 32 negative, for a GutVerdict score of 4.0/5. These are self-reported experiences, not clinical evidence.
15 of 177 rated owner comments (8%) describe an unwanted effect such as gas, bloating or an upset stomach. Check the safety notes on this page and ask a doctor or pharmacist before starting.
Most rated owner comments come from people in r/SIBO and others who mention SIBO (87 comments, 65 positive).
No. The score summarizes Reddit owner comments only. Factual statements on this page link to NIH or PubMed sources, and nothing here is medical advice.
“I started taking spore based probiotics lately because it's supposed to help with the health of the valve and it do believe it is helping.”
What owners report →
“One one of probiotics I was taking, LGG get rid of bilophila, but increased desulfovibrio.”
What owners report →
“when i started vsl#3, which is basically the same formula, it was like a crime scene in the bathroom for a solid ten days.”
What owners report →Comparisons: Saccharomyces boulardii vs L. rhamnosus GG (Culturelle) · Spore-based probiotics (Bacillus) vs Saccharomyces boulardii
Last updated 2026-11-03. Mentions scanned: 1922 in 1187 threads.