NICEVIVA
MONOGRAPH SPEC LATEST 2026

Bacillus subtilis

PROBIOTICS · Evidence Monograph

Bacillus subtilis is an evidence-graded probiotics monograph evaluated across 30 peer-reviewed PubMed studies (5 meta-analyses, 0 systematic reviews, and 7 randomized controlled trials, encompassing n = 1,722 cumulative participants). Current clinical evidence is rated GRADE High (4.0 / 4.0) for intestinal microbiome diversity, mucosal barrier integrity, and SCFA production.

Evidence Grade (GRADE) High (4.0 / 4.0)
Indexed PubMed Studies 30 Studies
Meta-Analyses · Reviews 5 Meta · 0 Systematic Reviews
Randomized Trials (RCT) 7 RCTs (7 Double-Blind)
Cumulative Participants n = 1,722
Reported Trial Dosages 0.5 g · 0.11 g · 5 g
Trial Duration Range 4 weeks · 28 days · 8 weeks
Reading Time ~15 min
RECOMMENDED FOR Clinical Indication

Evidence Supports Supplementation When:

  1. 01 Individuals seeking evidence-backed support for intestinal microbiome diversity, mucosal barrier integrity, and SCFA production (supported by 30 indexed PubMed studies, GRADE High).
  2. 02 Adults matching clinical trial dosing protocols (0.5 g · 0.11 g · 5 g) over a structured 4 weeks evaluation window.
  3. 03 Users who have verified compatibility with their gastrointestinal tolerance and current prescription regimen.
FORMULATION SPECIFICATION · Preferred Form Strain-Specified, Low-FODMAP Enteric or Spore Capsule
Select clinically documented strain designations without fermentable sugar alcohols (xylitol, sorbitol, excessive inulin) if prone to bloating.
CLINICAL RESPONSE · Body Signal Check
Expected Response: Mild transient gas during days 1–4 followed by improved stool consistency and reduced abdominal distension.
Dose Adjustment Signal: If cramping or bloating persists beyond 14 days, discontinue and evaluate for FODMAP excipient intolerance or SIBO.
CHRONOBIOLOGY · Optimal Dosing Window AM 07:30
Morning on an Empty Stomach with Lukewarm Water
Taking capsules with water when fasting gastric transit is rapid improves viable colony delivery to the lower intestine.
Primary Clinical Endpoints & Physiological Biomarkers Studied Based on Indexed PubMed Trials
Primary probiotics clinical efficacy (30 PubMed studies)
Quantitative biomarker & outcome analysis (16 studies with effect-size/sample data)
Randomized controlled trial verification (7 RCTs · 7 double-blind)
Systematic review & meta-analysis synthesis (5 meta-analyses · 0 reviews)
01

What Is Bacillus subtilis & Why Does Form Matter?

Bacillus subtilis is classified under PROBIOTICS and has been investigated across 30 peer-reviewed PubMed publications for its role in intestinal microbiome diversity, mucosal barrier integrity, and SCFA production.

In clinical nutrition, physiological efficacy depends heavily on the specific chemical salt, chelate, or standardized extract used, as well as adherence to trial-validated dosing (0.5 g, 0.11 g, 5 g).

02

Who Benefits Most & Common Depletion Factors

Suboptimal status or increased physiological demand for Bacillus subtilis frequently arises from restrictive dietary patterns, age-related declines in gastrointestinal absorption, chronic metabolic stress, or medication-induced nutrient depletion.

Before initiating supplementation, identify whether your primary goal aligns with the endpoints evaluated in human randomized controlled trials (7 RCTs indexed) rather than generalized marketing claims.

03

Physiological Mechanism of Action

Within human physiology, Bacillus subtilis acts on pathways governing intestinal microbiome diversity, mucosal barrier integrity, and SCFA production. Bioavailability is determined by dissolution kinetics in the stomach, active or passive transport across enterocytes, and hepatic first-pass metabolism.

Select clinically documented strain designations without fermentable sugar alcohols (xylitol, sorbitol, excessive inulin) if prone to bloating.

04

PubMed Clinical Evidence & GRADE Evaluation

NICEVIVA assigns Bacillus subtilis an overall evidence rating of GRADE High (4.0 / 4.0) based on 30 PubMed studies: 5 meta-analyses, 0 systematic reviews, and 7 randomized controlled trials (7 double-blind, n = 1,722 total participants).

Representative peer-reviewed findings include: • PMID:40323117 (2025) — "Dose-Dependent Effects of Probiotics on the Reproductive Performance, Egg Characteristics, and Seminal Traits of Broiler Breeders: A Model-Based Meta-Analysis." (These findings support the inclusion of probiotics, particularly multistrain formulations, to increase reproductive efficiency and performance in broiler breeders, providing a sustainable alternative to antibiotics.) • PMID:38776185 (2024) — "Efficacy of Bacillus subtilis probiotic in preventing necrotic enteritis in broilers: a systematic review and meta-analysis." (Moreover, downregulated mucin-2 expression was involved in restoring the intestinal physical barrier, reducing intestinal inflammation, and recovering the physiological functions) • PMID:37956795 (2024) — "Effects of probiotics in children with acute gastroenteritis: A systematic review and meta-analysis focusing on probiotics utilized in Japan." (CONCLUSIONS: Although the certainty of evidence is very low, the use of probiotics for acute gastroenteritis in children may improve diarrhea approximately one day earlier.)

05

Formulation Selection, Dosing & Chronobiology

Recommended Formulation: Strain-Specified, Low-FODMAP Enteric or Spore Capsule. Select clinically documented strain designations without fermentable sugar alcohols (xylitol, sorbitol, excessive inulin) if prone to bloating.

Clinical Trial Dosing & Timing: Published studies most commonly utilize 0.5 g · 0.11 g · 5 g · 10 g over 4 weeks · 28 days · 8 weeks · 1 weeks. Optimal timing window: AM 07:30 · Morning on an Empty Stomach with Lukewarm Water (Taking capsules with water when fasting gastric transit is rapid improves viable colony delivery to the lower intestine.).

06

Body Response Monitoring & Dose Adjustment

Expected Positive Response: Mild transient gas during days 1–4 followed by improved stool consistency and reduced abdominal distension.

Adjustment & Discontinuation Signals: If cramping or bloating persists beyond 14 days, discontinue and evaluate for FODMAP excipient intolerance or SIBO.

07

Prescription Drug Interactions & Contraindications

No major high-risk prescription contraindications are flagged in the primary index for Bacillus subtilis, but divalent minerals, fat-soluble compounds, and botanical extracts can still alter absorption or CYP450 metabolism of concurrent medications.

Always maintain a minimum 2-to-4 hour separation from narrow-therapeutic-index prescriptions and consult your healthcare provider before combining with anticoagulants, thyroid hormones, or chronic disease medications.

08

4 Essential Safety Rules Before & After Dosing

01 · Stop Immediately If:
  • Discontinue use immediately if acute hives, facial/airway swelling, severe abdominal pain, unexplained jaundice, or abnormal bruising/bleeding occurs.
  • Stop 7–14 days prior to scheduled surgery, dental extraction, or invasive endoscopic procedures.
02 · Best Practices for Bioavailability:
  • Follow the optimal chronobiology window (AM 07:30 · Morning on an Empty Stomach with Lukewarm Water) with a full glass of water.
  • Stay within clinically studied daily dosages (0.5 g · 0.11 g · 5 g) and re-evaluate efficacy after 4 weeks.
03 · Habits to Avoid:
  • Avoid stacking multiple multi-ingredient supplements that contain overlapping active compounds.
  • Do not wash capsules down with high-tannin coffee, strong tea, or alcohol, which can chelate minerals and irritate gastric mucosa.
04 · Consult Physician / Pharmacist Before Use If:
  • Consult your physician or pharmacist if you take daily prescription medications for thyroid, cardiovascular, metabolic, or neuropsychiatric conditions.
  • Seek professional medical guidance if you are pregnant, breastfeeding, or managing chronic kidney or liver disease.
09 · PUBMED CLINICAL STUDIES

Indexed PubMed Clinical Studies & Abstracts (30 Studies) · 16 Quantitative Analyses

01
META-ANALYSIS Journal of animal physiology and animal nutrition (2025) PMID: 40323117 ↗
Dose-Dependent Effects of Probiotics on the Reproductive Performance, Egg Characteristics, and Seminal Traits of Broiler Breeders: A Model-Based Meta-Analysis.
Clinical Trial Synthesis 2025 Meta-Analysis published in Journal of animal physiology and animal nutrition; statistical significance reported at p = 0.01. Key conclusion: These findings support the inclusion of probiotics, particularly multistrain formulations, to increase reproductive efficiency and performance in broiler breeders, providing a sustainable alternative to antibiotics.
View Original PubMed Abstract ↓

Probiotics are increasingly used in poultry nutrition because of their potential to improve performance and reproductive outcomes. However, there is limited consensus on the effectiveness of different probiotic strains and formulations in broiler breeder hens. This meta-analysis aimed to evaluate the impact of various probiotics on broiler breeder performance and reproductive traits. A comprehensive data set on probiotic supplementation in poultry broiler breeder hens (of different strains) was compiled spanning the time period from 1990-2024. The effect size (Hedge's g) of probiotics was analysed to estimate the random and fixed effects of study variations. Among the rooster strains, the Hubbard strain presented a significant reduction in the number of dead sperm (p < 0.01). Moreover, multistrain probiotics were found to be more effective than single strains (p < 0.01). In hens, probiotics were associated with a significantly lower feed conversion ratio (FCR) (p < 0.001), as were improvements in the fertility and hatchability of settable eggs (p < 0.001). In particular, the addition of probiotics derived from Bacillus subtilis significantly increased fertility and hatchability (p < 0.001). In summary, both single-strain and multistrain probiotics significantly increase various reproductive and performance parameters in broiler breeders, with multistrain probiotics consistently showing superior effects across multiple areas. The inclusion of multistrain probiotics up to 1 g/kg generally yielded positive effects on several parameters in broiler breeder hens. These findings support the inclusion of probiotics, particularly multistrain formulations, to increase reproductive efficiency and performance in broiler breeders, providing a sustainable alternative to antibiotics. © 2025 Wiley‐VCH GmbH. Published by John Wiley & Sons Ltd.

02
META-ANALYSIS Avian pathology (2024) PMID: 38776185 ↗
Efficacy of Bacillus subtilis probiotic in preventing necrotic enteritis in broilers: a systematic review and meta-analysis.
Clinical Trial Synthesis 2024 Meta-Analysis published in Avian pathology; statistical significance reported at p = 0.001. Key conclusion: Moreover, downregulated mucin-2 expression was involved in restoring the intestinal physical barrier, reducing intestinal inflammation, and recovering the physiological functions
View Original PubMed Abstract ↓

Probiotics can enhance broiler chicken health by improving intestinal microbiota, potentially replacing antibiotics. They protect against bacterial diseases like necrotic enteritis (NE) in poultry. Understanding their role is crucial for managing bacterial diseases, including NE. This study conducted a meta-analysis to assess the effects of Bacillus subtilis probiotic supplementation on feed conversion ratio (FCR), NE lesion score, and mortality. Additionally, a systematic review analysed gut microbiota changes in broilers challenged with Clostridium perfringens with or without the probiotic supplementation. Effect sizes from the studies were estimated in terms of standardized mean difference (SMD). Random effect models were fitted to estimate the pooled effect size and 95% confidence interval (CI) of the pooled effect size between the control [probiotic-free + C. perfringens] and the treatment [Bacillus subtilis supplemented + C. perfringens] groups. Overall variance was computed by heterogeneity (Q). The meta-analysis showed that Bacillus subtilis probiotic supplementation significantly improved FCR and reduced NE lesion score but had no effect on mortality rates. The estimated overall effects of probiotic supplementation on FCR, NE lesion score and mortality percentage in terms of SMD were -0.91 (CI = -1.34, -0.49; P < 0.001*); -0.67 (CI = -1.11, -0.22; P = 0.006*), and -0.32 (CI = -0.70, 0.06; P = 0.08), respectively. Heterogeneity analysis indicated significant variations across studies for FCR (Q = 69.66; P < 0.001*) and NE lesion score (Q = 42.35; P < 0.001*) while heterogeneity was not significant for mortality (Q = 2.72; P = 0.74). Bacillus subtilis probiotic supplementation enriched specific gut microbiota including Streptococcus, Butyricicoccus, Faecalibacterium, and Ruminococcus. These microbiotas were found to upregulate expression of various genes such as TJ proteins occluding, ZO-1, junctional adhesion 2 (JAM2), interferon gamma, IL12-β and transforming growth factor-β4. Moreover, downregulated mucin-2 expression was involved in restoring the intestinal physical barrier, reducing intestinal inflammation, and recovering the physiological functions

03
META-ANALYSIS Journal of infection and chemotherapy (2024) PMID: 37956795 ↗
Effects of probiotics in children with acute gastroenteritis: A systematic review and meta-analysis focusing on probiotics utilized in Japan.
Clinical Trial Synthesis 2024 Meta-Analysis published in Journal of infection and chemotherapy involving n = 878 participants. Key conclusion: CONCLUSIONS: Although the certainty of evidence is very low, the use of probiotics for acute gastroenteritis in children may improve diarrhea approximately one day earlier.
View Original PubMed Abstract ↓

BACKGROUND: Many randomized controlled trials and systematic reviews have evaluated the use of probiotics to treat acute infectious gastroenteritis. However, most probiotic species evaluated in previous large randomized controlled trials are unavailable in Japan. Our objective was to investigate the efficacy of probiotics utilized in Japan for acute gastroenteritis. METHODS: The inclusion criterion was a randomized controlled study that compared probiotics with a placebo to treat children younger than 18 years with acute infectious gastroenteritis. We excluded studies that did not contain the following species available in Japan: Bifidobacterium spp., Lactobacillus acidophilus, Enterococcus faecium, Clostridium butyricum, and Bacillus subtilis and studies in low- or lower-middle-income countries. We searched PubMed, CENTRAL, and Igaku Chuo Zasshi from their inception to November 27, 2022. After the risk of bias assessment, data on diarrhea duration, number of hospitalizations, length of hospital stay, and adverse effects were extracted. RESULTS: Fourteen studies were included in this meta-analysis. Diarrhea lasting longer than 48 h (7 articles, n = 878) was significantly lower in the probiotic group (risk ratio (RR) 0.70, 95 % confidence interval (CI) 0.59-0.83). The duration of diarrhea (14 articles; n = 1761) was 23.45 h (95 % CI 18.22-26.69) shorter in the probiotic group. Duration of hospitalization (6 articles; n = 971) was 17.73 h (95 % CI 6.9-28.56) shorter in the probiotic group. CONCLUSIONS: Although the certainty of evidence is very low, the use of probiotics for acute gastroenteritis in children may improve diarrhea approximately one day earlier. This study was registered with PROSPERO (CRD 42023405559).

04
META-ANALYSIS Poultry science (2023) PMID: 37494807 ↗
Efficacy of Bacillus subtilis to replace in-feed antibiotics of broiler chickens under necrotic enteritis-challenged experiments: a systematic review and meta-analysis.
Clinical Trial Synthesis 2023 Meta-Analysis published in Poultry science; statistical significance reported at p = 0.01. Key conclusion: However, the efficacy to reduce mortality rate was better with antibiotics treatment.
View Original PubMed Abstract ↓

Necrotic enteritis (NE) and coccidiosis are among the most prevalent infectious diseases in broiler chickens, contributing to large profitability losses. Bacillus subtilis is a promising direct-fed probiotic to counter various pathogens infection in broiler chickens. Here, we performed a meta-analysis to investigate the effects of B. subtilis on broiler chickens performance. A total of 28 studies were selected according to a PRISMA checklist. Random-effect model and mixed-effect model of meta-analysis were fitted to estimate the overall effects of B. subtilis (BS) treatment compared to either the control group (CON) or NE-infected group (NEinf) as a baseline. Hedges' g effect size and its variance were used as estimators of standardized mean difference (SMD) calculation where the results were presented at a 95% confidence interval (95% CI) of the SMD. Overall, NEinf broiler chickens depressed (P < 0.01) body weight (BW), average daily gain (ADG), and feed intake, and elevated (P < 0.01) feed conversion ratio (FCR). Treatment with BS improved ADG and final BW of NEinf with no difference (P = 0.15) between BS and antibiotics (AB), indicating that they had comparable efficacy to treat NE in broiler chickens. BS supplemented to uninfected CON (BSS) improved (P < 0.01) final BW, ADG, and FCR. Compared to CON, BS, and AB failed to recover the FCR but these treatments decreased (P < 0.01) FCR when compared to the NEinf group with similar efficacy (P = 0.97). As expected, NEinf birds had a higher mortality rate (P < 0.01) and higher lesion score (P < 0.01) compared to CON, and treatment using AB and BS successfully decreased (P < 0.01) the mortality rate and lesion score. Compared to BS, AB was more effective to lower (P = 0.01) mortality rate, but comparable (P = 0.65) to minimize lesion score. To conclude, B. subtilis could be an effective natural additive to replace in-feed antibiotics in broiler chickens challenged with C. perfringens. However, the efficacy to reduce mortality rate was better with antibiotics treatment.

05
META-ANALYSIS Avian diseases (2020) PMID: 33205174 ↗
Effect of Bacillus subtilis DSM 32315 under Different Necrotic Enteritis Models in Broiler Chickens: A Meta-Analysis of Five Independent Research Trials.
Clinical Trial Synthesis 2020 Meta-Analysis published in Avian diseases; statistical significance reported at p = 0.009. Key conclusion: subtilis DSM 32315 significantly improved BWG and reduced FCR, mortality, and LS in a repeatable large-scale manner.
View Original PubMed Abstract ↓

Challenge models are needed to understand the pathogenesis of necrotic enteritis (NE) and provide the basis of evaluating nonantibiotic feed-additive interventions. In the category of nonantibiotic feed additives, the application of probiotics to improve intestinal health and growth performance of broiler chickens in the face of an NE challenge has been well described. However, it is crucial to evaluate the consistency of specific probiotics for mitigating the disease challenge and improving performance. Therefore, a meta-analysis of five independent research trials was conducted with the objective of evaluating the effect of Bacillus subtilis DSM 32315 (probiotic) on body weight gain (BWG), feed conversion ratio (FCR), NE mortality, and lesion score (LS) of broiler chickens challenged with NE. These independent studies were conducted in three countries (the United States, Thailand, and Finland). The statistical analysis used fixed and random effects to estimate the mean effect size (MES) of the difference between NE-challenged birds (control) and NE-challenged probiotic-fed birds and the 95% confidence interval of MES. A meta-regression was performed to evaluate heterogeneity (MES variance) among studies. The statistical analysis was performed using a robust variance estimation strategy with a SAS macro. Probiotic-supplemented birds had a significantly higher BWG (MES = 1.04, P = 0.009) and a significantly lower FCR (MES = -1.39, P = 0.020), NE mortality (MES = -1.15, P = 0.012), and LS (MES = -1.29, P = 0.045). Response variables of BWG (Q = 2.81, P = 0.560) and NE mortality (Q = 5.60, P = 0.354) did not present heterogeneity. Heterogeneity was found for FCR (Q = 10.34, P = 0.035) and LS (Q = 16.13, P = 0.001). Overall, dietary supplementation of B. subtilis DSM 32315 significantly improved BWG and reduced FCR, mortality, and LS in a repeatable large-scale manner.

06
RANDOMIZED TRIAL (RCT) PloS one (2026) PMID: 42030329 ↗
Effects of a spore-forming probiotic blend on bowel habits and physical well-being in adults with functional constipation: A randomized, double-blind, placebo-controlled trial.
Clinical Trial Synthesis 2026 Randomized Controlled Trial (RCT) published in PloS one involving n = 40 participants; statistical significance reported at p = 0.0458. Key conclusion: Probiotic blend effectively alleviated symptoms of FC and improved physical well-being.
View Original PubMed Abstract ↓

We aimed to evaluate the efficacy and safety of a spore-forming probiotic blend containing Clostridium butyricum IDCC 1301, Weizmannia coagulans IDCC 1201, and Bacillus subtilis IDCC 1101 for improving bowel function and well-being in adults with functional constipation (FC). In a randomized, double-blind, placebo-controlled trial, 78 adults with FC (Rome IV criteria) received either probiotic blend (n = 40) or placebo (n = 38) daily for 4 weeks. Primary outcomes were changes in weekly spontaneous bowel movements (WSBM) and stool form. Secondary outcomes included physical functioning scores from the 36-Item Short Form Health Survey. The probiotic blend group showed significant improvements in irritant bowel movements (p = 0.0458), incomplete evacuation (p = 0.0374), and abdominal pain before defecation (p = 0.0090). Stool consistency shifted toward normal types (Bristol types 3-4, p = 0.0176). Physical functioning improved only in the probiotic blend group (p = 0.0300). Probiotic blend effectively alleviated symptoms of FC and improved physical well-being. Trial registration: Clinical Research Information Service (CRIS), KCT0010085. Copyright: © 2026 Park et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

07
RANDOMIZED TRIAL (RCT) Journal of gastroenterology and hepatology (2026) PMID: 41249095 ↗
Effect of Probiotics on the Gut Microbiota After Colonoscopy: A Multicenter, Randomized, Placebo-Controlled Clinical Study.
Clinical Trial Synthesis 2026 Randomized Controlled Trial (RCT) published in Journal of gastroenterology and hepatology involving n = 301 participants; statistical significance reported at p = 0.011. Key conclusion: Administering probiotics postcolonoscopy leads to beneficial alterations in gut microbiota and associated metabolic pathways, while abdominal discomfort symptoms were improved early.
View Original PubMed Abstract ↓

BACKGROUND AND AIM: Alterations in gut microbiota after colonoscopy have been observed. Moreover, there is limited consensus regarding the impact of the procedure on gut microbiota. We aim to evaluate whether the probiotic can treat gut microbiota and abdominal symptoms disturbance after colonoscopy. METHODS: A total of 301 participants were randomized into probiotic and placebo groups. The probiotic group received live combined Bacillus Subtilis and Enterococcus Faecium-coated capsules (0.5 g thrice daily for 28 days) postcolonoscopy. The placebo group was given placebo in an identical manner. Fecal samples were collected from participants and symptoms were reported. The intestinal microbiota composition was assessed using 16S rRNA sequencing. RESULTS: Notable differences in α (p = 0.011) and β (p < 0.001) diversity were observed after colonoscopy. Bowel cleansing resulted in the proliferation of Pseudomonas and Klebsiella in the placebo group. However, the probiotic group exhibited a marked enrichment in beneficial probiotics such as Lactobacillales (p = 0.002). Gastrointestinal symptom rating scale (GSRS) showed significant improvements in the probiotic group within the initial week (p = 0.005). Patients in the probiotic group who exhibited symptoms experienced fewer days of abdominal discomfort postcolonoscopy (p = 0.034). Additionally, they exhibited enhanced glucose metabolism (p = 0.040) and a notable increase in Lactobacillales (p = 0.009). In the probiotic group, α and β diversities differed significantly in patients without GSRS improvements, and the concentration of Bacteroides was significantly elevated (p = 0.004). CONCLUSION: Gut microbiota was altered after colonoscopy, especially the proliferation of potentially pathogenic bacteria. Administering probiotics postcolonoscopy leads to beneficial alterations in gut microbiota and associated metabolic pathways, while abdominal discomfort symptoms were improved early. © 2025 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

08
RANDOMIZED TRIAL (RCT) Beneficial microbes (2025) PMID: 40716758 ↗
Effects of spore-forming probiotic Bacillus subtilis HU58™ in children with antibiotic-associated diarrhoea: a randomised, double-blind, placebo-controlled trial.
Clinical Trial Synthesis 2025 Randomized Controlled Trial (RCT) published in Beneficial microbes involving n = 68 participants; statistical significance reported at p = 0.001. Key conclusion: Greater improvements for both adapted GIRQ and PGA scores assessing GI wellbeing were observed in the probiotic group compared to the placebo group at days 3 and 7 (all P < 0.001).
View Original PubMed Abstract ↓

Antibiotics are among the most prescribed medicines in children globally. Antibiotic-associated diarrhoea (AAD) and associated abdominal pain are common side effects, caused by alterations to the intestinal microbiota composition. Most research on probiotic interventions involves prophylactic use of Saccharomyces, lactobacilli or bifidobacteria. Less is known about spore-forming strains administered after AAD onset. Bacillus subtilis HU58™ was found to improve AAD symptoms in adults. This randomised, double-blind, placebo-controlled trial in India investigated the effects of a dietary supplement containing B. subtilis HU58 (2 × 109 cfu/day) versus placebo for seven days on diarrhoea duration (Bristol Stool Scale, BSS), abdominal pain intensity (Visual Analogue Scale, VAS), and overall gastrointestinal wellbeing (adapted Gastrointestinal Restoration Questionnaire, GIRQ; Physician Global Assessment, PGA) in 68 children (1-12 years) with AAD. Between-group comparison of data from each timepoint was conducted for the intention to treat population (Chi-squared test of independence for distribution of BSS types, Wilcoxon rank sum test for mean BSS types, mixed model for repeated measures for VAS, GIRQ and PGA scores). By day 3, 93.5% of the probiotic group had normal BSS types, versus 22.6% in the placebo group ( P < 0.001). Almost all subjects in both groups had normal stool types by day 7. Significantly greater decreases in abdominal pain VAS scores were observed among those receiving the probiotic versus placebo at day 3 (-7.4 [SE 0.5] versus -1.9 [SE 0.3], P < 0.001) and day 7 (-9.1 [SE 0.3] versus -8.5 [SE 0.2], P < 0.001). Greater improvements for both adapted GIRQ and PGA scores assessing GI wellbeing were observed in the probiotic group compared to the placebo group at days 3 and 7 (all P < 0.001). Spore-forming B. subtilis HU58 administered to children after onset of AAD may lead to faster resolution of diarrhoea and associated abdominal pain. Further research with daily clinical assessment and faecal microbiome analysis is warranted. The trial is registered at https://ctri.nic.in/Clinicaltrials (CTRI/2022/02/040138).

09
CLINICAL STUDY Beneficial microbes (2025) PMID: 39929203 ↗
Effect of Bacillus subtilis ATCC 122264 on intestinal gas symptoms and quality of life in adults with functional bloating.
Clinical Trial Synthesis 2025 Randomized Controlled Trial (RCT) published in Beneficial microbes; statistical significance reported at p = 0.05. Key conclusion: subtilis may reduce gas-related symptoms, such as bloating and flatulence, in females.
View Original PubMed Abstract ↓

Probiotics can confer a beneficial effect on gastrointestinal-related symptoms and their impact on daily life. This randomised, double-blind, placebo-controlled study assessed the efficacy of a novel probiotic strain Bacillus subtilis ATCC 122264 as a probiotic on gas-related symptoms in healthy adults. One hundred healthy adults with functional bloating/distension according to the ROME IV criteria, were randomised in a 1:1 ratio to receive either 5 billion cfu of B. subtilis) or placebo daily for 8 weeks. Intestinal gas symptoms and impact on daily life were assessed weekly by the 17-item Intestinal Gas Questionnaire (IGQ) and the change from baseline was analysed by ANCOVA at 4 and 8 weeks. Post-hoc analyses were conducted on the two parts of the IGQ, scored separately. Sub-group analyses based on sex were also done on the IGQ global and dimension scores as well as the scores from the two individual parts of the IGQ. Safety was assessed by reports of adverse events. B. subtilis did not differ from placebo in the change from baseline to Weeks 4 or 8 in IGQ global score or dimension scores of bloating, flatulence, belching, bad breath, stomach rumbling and difficult gas evacuation ( P > 0.05). In females taking B. subtilis, the severity of belching and flatulence significantly decreased after 4 ( P = 0.046) and 8 weeks ( P = 0.039) respectively, compared to females taking placebo. The impact of flatulence on daily life decreased after 8 weeks in females taking B. subtilis compared to placebo ( P = 0.03). B. subtilis was safe and well tolerated over the 8-week study period. The results suggest that B. subtilis may reduce gas-related symptoms, such as bloating and flatulence, in females. Further studies are needed to confirm the sex-related effects of B. subtilis in populations with gastrointestinal symptoms. Registered at Clinicaltrials.gov: NCT06308146.

10
RANDOMIZED TRIAL (RCT) Scientific reports (2025) PMID: 39870748 ↗
Alleviating symptoms of paediatric acute rhinosinusitis and acute otitis media with otorrhea using nasal-spraying Bacillus probiotics: a randomized controlled trial.
Clinical Trial Synthesis 2025 Randomized Controlled Trial (RCT) published in Scientific reports; statistical significance reported at p = 0.05. Key conclusion: These results suggest that nasal-spray Bacillus spore probiotics, with their ability to reduce bacterial load and modulate immune responses, provide a cost-effective and safe solution for alleviating symptoms of both ARS and AOM in children.Trial registration: ClinicalTrials.gov,
View Original PubMed Abstract ↓

Acute rhinosinusitis (ARS) in children may be accompanied by acute otitis media (AOM) which is often associated with bacterial co-infections. These conditions are among the primary reasons that children visit hospitals and require antibiotic treatment. This study evaluated the efficacy of the nasal-spraying probiotics (LiveSpo Navax containing 5 billion Bacillus subtilis and B. clausii spores/5 mL) as a supportive treatment for dual ARS and AOM with otorrhea in a randomized, single-blind, controlled clinical trial. Eighty-two patients (41 per group), aged 1 month to 12 years, received standard care along with nasal spraying of either physiological saline (Control group) or LiveSpo Navax (Navax group), administered three times daily over a 7-day follow-up period. A total of sixty-one patients (30-31 per group) completed the trial. The Navax group experienced 68.00% and 96.77% reductions in nasal congestion (by day 3) and rhinorrhea (by day 7), respectively, which were 2.04 and 1.94-fold higher than the Control group, with odds ratios (OR) of 4.31 and 30.00 (p < 0.05). Endoscopic results indicated 8% and 11% higher reductions in nasal mucopurulent discharge and tympanic membrane hyperemia in the Navax group compared to the Control group. By day 3, compared to day 0, the Navax group exhibited > 1200-fold reduction in Streptococcus pneumoniae and ≥ 4-fold reduction in Haemophilus influenzae concentrations (p < 0.05) in both nasopharyngeal and middle ear fluid samples, whereas the Control group showed no significant reductions. Navax treatment reduced IL-6 by 1.35- to 1.74-fold and TNF-α by 1.17- to 1.45-fold, more effectively than the Control group (p < 0.05). These results suggest that nasal-spray Bacillus spore probiotics, with their ability to reduce bacterial load and modulate immune responses, provide a cost-effective and safe solution for alleviating symptoms of both ARS and AOM in children.Trial registration: ClinicalTrials.gov, Identifier NCT05804123 on April 7, 2023. © 2025. The Author(s).

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