Probiotics
Saccharomyces boulardii
4.0 (478 owner comments)
Urgency & loose stoolsBloating & gas
“I've tolerated taking Florastor 3x a day during antibiotics.”
What owners report →Medical disclaimer: GutVerdict summarizes what people say about supplements on Reddit. It is not medical advice, and nothing here is meant to diagnose, treat, cure, or prevent any disease. These statements have not been evaluated by the Food and Drug Administration. Talk to your doctor or pharmacist before starting a supplement, especially if you are pregnant, take medicines, or have a medical condition. New, severe or worsening symptoms (such as blood in the stool, weight loss, fever, or night-time symptoms) need a doctor, not a supplement. Full disclaimer.
Probiotics · capsules
Spore-based probiotics (Bacillus): What People With IBS Report on Reddit
Illustration, not a product photo.
Probiotics made of Bacillus spores, which survive stomach acid as dormant spores.
4.2 GutVerdict score
194 owner comments (83 with a clear rating) from r/SIBO, r/Microbiome, r/IBS, r/Constipation, r/Supplements, November 2025 to October 2026. Top 9% of the 36 rated supplements.
Owner sentiment3.9
Recommendations3.7
Tolerability4.8
ValueNot rated
Value is not rated: the example products differ too much in dose to compare cost fairly. How we score.
The short version
Spore-based probiotics (Bacillus) is among the better-rated supplements we track: 4.2/5. Of 83 rated owner comments, 69 were positive, 3 mixed and 11 negative; 7 mention an unwanted effect. People talk most about bloating & gas and pain & cramping.
Reddit comments are self-reported and unverified. They tell you what people noticed, not whether a supplement works or is safe for you.
Our probiotic strain guide compares Align, Culturelle and Florastor. Reddit owners also rank supplements by constipation reports. There is a separate ranking of what people with SIBO rate highest.
What it is
- Bacillus species form spores, which helps them survive storage and stomach acid.[PubMed]
Safety and interactions
- The NIH notes probiotics may not be safe for people who are very ill or have a poorly functioning immune system; ask a doctor first.[NCCIH]
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.
Reports by symptom
| Context | Rated owner comments | Positive | Negative | Unwanted effects |
|---|---|---|---|---|
| SIBO | 38 | 30 | 7 | 3 |
| IBS-C & constipation | 17 | 16 | 1 | 0 |
| Bloating & gas | 17 | 13 | 4 | 0 |
| Pain & cramping | 7 | 6 | 0 | 1 |
| After antibiotics | 6 | 5 | 1 | 0 |
| IBS-D & loose stools | 4 | 2 | 0 | 2 |
What Reddit owners say
Commonly praised
- Bloating & gas: 9 owner comments
- Pain & cramping: 4 owner comments
- Regularity: 2 owner comments
Common complaints
- Side effects: 5 owner comments
- Bloating & gas: 4 owner comments
- Regularity: 1 owner comment
4/5“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.”
4/5“bacillus coagulans has been really good for me and mine.”
5/5“consider bacillus coagulans. it's said to sort of organize the thing - tamping down overgrowers, boosting laggards, helping with biofilms, more. it's been amazing for me and mine.”
2/5 Bloating & gas“I have/had similar symptoms and tried all those probiotics including some fancy ones like HU58 spore based ones and etc, probiotics never helped (and probiotic food like kimchi and fermented stuff would give me insane gas and acne).”
1/5“you might consider bacillus coagulans, a top ranked probiotic for issues like yours.”
+30 more owner comments
4/5“Spore based probiotics can be harmful or helpful depending on the person's unique microbiome.”
4/5“If you do another elemental diet I'd recommend taking biofilm disruptors and megasporebiotic.”
3/5 Urgency & loose stools“However I take the Just Thrive probiotics and I notice a HIGE difference on those.”
5/5“consider probiotic bacillus coagulans. it's got some strong sci papers on pubmed vs ibs. it's been amazing for me and mine.”
5/5“the spore probiotic bacillus coagulans has been amazing for me and mine.”
4/5“we also take a capsule/day of bacillus coagulans.”
3/5 Side effects“When I was looking into taking megaspore a while back I had concerns about B.”
4/5“Since you just started the spore based and stopped the Accutane hopefully you will feel better soon!”
4/5“Megaspore probiotic has been great for me.”
4/5 Regularity“Using: Lactobacillus Bifidobacterium, Saccaromyces Boulardii, and a spore-based probiotic like, Bacillus Subtilus.”
2/5 Bloating & gas“I have dysbiosis as well and my doctor tried me on a tiny sprinkle of MegaSpore probiotic and I had such a bad reaction with bloating after two weeks I had to stop.”
5/5“bacillus coagulans has some GREAT papers vs ibs published on pubmed.”
5/5“bacillus coagulans has some strong sci papers/trials vs ibs on pubmed.”
5/5“might look at this probiotic, bacillus coagulans - well studied vs ibs and it's been amazing for me and mine.”
5/5“and this probiotic is amazing for us - bacillus coagulans”
4/5“I’m a daily consumer of kombucha, yogurt, kefir and take spore based probiotic supplements and I take prebiotic fiber (Heather’s Tummy Fiber in addition to a pretty healthy diet.”
2/5“bacillus coagulans has been nothing short of amazing for me and mine.”
4/5“Megasporebiotic helped me in so many ways”
5/5“bacillus coagulans has been a miracle for me and mine”
4/5“and you left out the best single strain i've found - bacillus coagulans.”
4/5“I originally started taking Bacillus coagulans (BC-30) for its potential to improve essential amino acid absorption, reduce muscle soreness, and enhance recovery after intense training.”
4/5“also think bacillus coagulans supp did a lot of heavy lifting for me.”
4/5“the exception are the spore bacteria, like bacillus coagulans.”
4/5 Bloating & gasPain & cramping“I started spore based probiotics and saw the biggest improvement in bloating and pain in only a few days.”
4/5 Bloating & gas“The Biome protect does continue to speed up my motility (the main probiotic is bacillus coagulans which now I notice is also used in other debloat type probiotics out there.) which makes me feel better all around.”
2/5“The probiotics I took were megasporebiotic and s boulardi.”
4/5“What helped me sleep and lower my anxiety was taking probiotics (without gums or prebiotics) like just thrives, and staying away from foods like gums (emulsifiers), vegetables, corn, usually fiber heavy carbs, dried dates and a few other foods.”
4/5“S boulardii didnt make a difference for me, I am trying Bacillus subtilis HU58 right now and it seems to be helping.”
4/5“No, but i use Bacillus subtilis HU58 from microbiome lab and it helps me”
4/5 Bloating & gasPain & cramping“I started taking bacillus coagulans about a month ago.”
Brands with their own owner reviews
- Just Thrive: 3.2 from 28 owner comments
Example products
These are examples of Spore-based probiotics (Bacillus) 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.
Example product · not Reddit-scored
Just Thrive Probiotic & Antioxidant 100% Spore-Based Digestive Support
Brand on Reddit: 3.2 from 28 owner comments · Just Thrive owner reviews
$133.99 on Amazon (price as of 2026-11-03). Prices change; check Amazon for the current price.
Example product · not Reddit-scored
THORNE Bacillus Coagulans, Shelf-Stable Vegan Probiotic, 60 Capsules
$33.00 on Amazon (price as of 2026-11-03). Prices change; check Amazon for the current price.
Example product · not Reddit-scored
Microbiome Labs Mega SporeBiotic Daily Probiotic for Women + Men, 60 Ct
$66.25 on Amazon (price as of 2026-11-03). Prices change; check Amazon for the current price.
Research to read
Published studies (we list them so you can read the evidence yourself; inclusion is not an endorsement):
- Benef Microbes 2019: Bacillus coagulans and its applications in medicine.
- Gastroenterology 2023: Efficacy of Probiotics in Irritable Bowel Syndrome: Systematic Review and Meta-analysis.
FAQ
What do people with IBS say about Spore-based probiotics (Bacillus) on Reddit?
Across 194 Reddit comments from people who say they have used it, 69 of 83 rated comments were positive and 11 negative, for a GutVerdict score of 4.2/5. These are self-reported experiences, not clinical evidence.
Do people report side effects with Spore-based probiotics (Bacillus)?
7 of 83 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.
Who talks about Spore-based probiotics (Bacillus) most?
Most rated owner comments come from people in r/SIBO and others who mention SIBO (38 comments, 30 positive).
Is Spore-based probiotics (Bacillus) scored on clinical evidence?
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.
Related supplements
Probiotics
L. rhamnosus GG (Culturelle)
3.9 (53 owner comments)
CostSide effects
“One one of probiotics I was taking, LGG get rid of bilophila, but increased desulfovibrio.”
What owners report →
Probiotics
High-potency multi-strain (VSL#3 / Visbiome)
3.7 (70 owner comments)
CostSide effects
“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: Spore-based probiotics (Bacillus) vs Saccharomyces boulardii
Last updated 2026-11-03. Mentions scanned: 782 in 569 threads.