Bacillus clausii (Enterogermina® / Erceflora)

Bacillus clausii — strains O/C, N/R, SIN, T
Evidence Level
Strong
3 Clinical Trials
8 Documented Benefits
4/5 Evidence Score

Spore-forming bacterium with intrinsic POLY-ANTIBIOTIC RESISTANCE. Commercialized as ENTEROGERMINA® (Sanofi) globally + Erceflora (Philippines) — 2×10^9 spores per capsule lyophilized. STRAINS O/C, N/R, SIN, T characterize the standard preparation. PMC12182463 SYSTEMATIC REVIEW + META-ANALYSIS of 11 RCTs in pediatric ACUTE GASTROENTERITIS — Enterogermina vs ORT: SHORTENED diarrhea duration + REDUCED stool number + SHORTENED hospital stay. PMC7680487 H. PYLORI eradication therapy 130-pt RCT — incidence of week-1 diarrhea 29% vs 48% placebo (RR 0.61, 95% CI 0.39-0.97, p=0.03). PMC8994895 phase 3 INDIA pediatric acute diarrhea trial. NCT00447161 PADRE Filipino antibiotic-associated diarrhea trial. Antibiotic-resistant probiotic — IDEAL for AAD prevention concurrent with antibiotics.

Studied Dose ENTEROGERMINA® STANDARD: 2×10^9 spores per capsule/vial, 2-3 times daily during antibiotic therapy or for diarrhea management. PMC7680487 H. PYLORI TRIAL: 1 capsule (2×10^9 spores) 3× daily for 2 weeks. PMC8994895 INDIA PEDIATRIC: 2 billion spores per 5 mL bottle, twice daily for 5 days. NCT00447161 PADRE FILIPINO: 1×10^9 spores twice daily. ADULT AAD PREVENTION: 6×10^9 spores/day (per systematic review). PEDIATRIC AAD: 4×10^9 spores/day. STANDARD CONSUMER USE: 2-6 ×10^9 spores/day in divided doses. Take preferably AT TIME OF ANTIBIOTIC DOSING (intrinsic antibiotic resistance allows concurrent administration). Onset: AAD prevention immediate (concurrent with antibiotics); GI effects within hours-days. Long-term safety: 28-day mouse NOAEL >2000 mg/kg (5×10^11 CFU); extensive Italian/Philippine clinical use record. Pregnancy/lactation: limited specific data; consult physician.
Active Compound Bacillus clausii spores — strains O/C, N/R, SIN, T characterize Enterogermina® preparation. Polyantibiotic-resistant spore-forming bacterium

Benefits

Pediatric acute gastroenteritis 11-RCT META-ANALYSIS (PMC12182463)

PMC12182463 — SYSTEMATIC REVIEW + META-ANALYSIS of 11 RANDOMIZED CONTROLLED TRIALS + 3 non-randomized controlled trials. Population: children with acute gastroenteritis. Intervention: Enterogermina® (B. clausii O/C, N/R, SIN, T) vs ORT (Oral Rehydration Therapy) ± zinc. RESULTS: SOLID EVIDENCE that Enterogermina vs ORT (with or without zinc) SHORTENED DURATION OF DIARRHEA + REDUCED NUMBER OF STOOLS + SHORTENED DURATION OF HOSPITAL STAY. Less robust favorable evidence on stool consistency, vomiting, fever. Foundational meta-analytic evidence — most rigorous probiotic evidence base for pediatric acute gastroenteritis.

H. pylori eradication therapy diarrhea reduction (PMC7680487 130-pt RCT)

PMC7680487 (Infect Dis Ther 2020) — randomized double-blind single-center phase IIIB study in 130 adult outpatients with H. pylori infection (Italy). 1 Enterogermina® capsule (2×10^9 spores) or placebo 3 times daily for 2 weeks during clarithromycin 500 mg + amoxicillin 1 g + rabeprazole 20 mg twice daily eradication therapy. RESULTS: WEEK-1 DIARRHEA INCIDENCE 29% in B. clausii group vs 48% in placebo group (RR 0.61, 95% CI 0.39-0.97, p=0.03). Diarrhea remained lower throughout. Foundational adult AAD prevention evidence.

AAD prevention systematic review (Mdpi 14:439)

Mdpi 14:439 (2024) — SYSTEMATIC REVIEW of B. clausii (O/C, N/R, SIN, T) for AAD prevention. 4 studies: 2 RCTs, 1 meta-analysis of RCTs, 1 expert consensus. Children dose 4×10^9; adults 6×10^9. Outcomes: reduced diarrhea, stomach discomfort, abdominal pain, nausea, vomiting during antibiotic therapy. Spore-forming bacterium RESISTANT to GASTROINTESTINAL CONDITIONS + most commonly used antibiotics — promising approach for AAD.

India pediatric acute diarrhea phase 3 RCT (PMC8994895)

PMC8994895 — phase 3 randomized double-blind placebo-controlled study in INDIA. Patients aged 6 months to 5 years with ACUTE MODERATE DIARRHEA (WHO 2005 definition) <48h duration. B. clausii probiotic (Enterogermina® oral suspension 2 billion spores per 5 mL) twice daily for 5 days vs placebo, plus ORT and zinc. Foundational pediatric Indian-population evidence supporting global use of preparation.

Filipino antibiotic-associated diarrhea PADRE trial (NCT00447161)

NCT00447161 PADRE — phase 4 multicenter randomized open-label clinical trial in hospitalized immunocompetent FILIPINO INFANT/CHILDREN. Bacillus clausii (Erceflora) 1×10^9 spores twice daily vs no treatment for AAD prevention. Sponsor: Sanofi. Important pediatric AAD evidence in Asian population.

Polyantibiotic resistance (intrinsic mechanism advantage)

Bacillus clausii (O/C, N/R, SIN, T) has INTRINSIC POLYANTIBIOTIC RESISTANCE — survives concurrent administration with most commonly used antibiotics. Distinguishing pharmacological advantage: probiotic remains viable during antibiotic therapy unlike most Lactobacillus/Bifidobacterium strains which are killed by antibiotics. Enables CONCURRENT dosing for AAD prevention.

Spore-forming heat/acid resistance (delivery advantage)

B. clausii forms SPORES — resistant to heat, acidity (gastric pH), bile salts. Spores survive transit to lower GI tract where they germinate. Mechanism: efficient delivery to site of action without need for enteric coating. Practical pharmaceutical advantage.

Safety profile (NOAEL >2000 mg/kg)

Toxicology studies in mice: NOAEL (No Observed Adverse Effect Level) >2000 mg/kg and 1000 mg/kg (5×10^11 CFU) over 28 days. No body weight changes, clinical signs, hematological changes, biochemistry changes, gross/histopathology changes. Foundational safety evidence supporting pediatric + adult applications.

Mechanism of action

1

Intrinsic polyantibiotic resistance (UNIQUE)

B. clausii (O/C, N/R, SIN, T) has INTRINSIC POLYANTIBIOTIC RESISTANCE — survives concurrent administration with most commonly used antibiotics. Distinguishing pharmacological advantage allowing CONCURRENT antibiotic + probiotic administration. Foundation mechanism for AAD prevention.

2

Spore-forming durability

Forms heat/acid/bile-resistant SPORES — survives gastric transit and germinates in lower GI tract. No enteric coating required. Pharmaceutical advantage for room-temperature storage + delivery efficiency.

3

Antimicrobial peptide production

B. clausii produces antimicrobial peptides + bacteriocin-like substances active against various pathogens including C. difficile. Mechanism: competitive exclusion + direct antimicrobial activity reducing pathogen overgrowth during dysbiosis.

4

Microbiota restoration during dysbiosis

Restores gut microbiota balance during antibiotic-induced dysbiosis. Mechanism: niche occupation + competitive exclusion of pathogenic species + fermentative metabolic activity supporting commensal flora recovery.

5

Anti-inflammatory effects

Modulates gut inflammatory response — reduces pro-inflammatory cytokines + supports mucosal immune regulation. Mechanism for symptomatic relief in acute gastroenteritis beyond pure antimicrobial effects.

6

Frequency of defecation reduction

Mouse castor oil-induced diarrhea model: B. clausii PBC429™ REDUCED frequency of defecation, onset of diarrhea, total fecal weight, percentage of defecation. Mechanism: combined antimicrobial + mucosal protective + gut motility modulation.

Clinical trials

1
PMC12182463 — Enterogermina Pediatric Acute Gastroenteritis META-ANALYSIS (PIVOTAL)
PubMed

Systematic review + meta-analysis (PMC12182463). 11 randomized + 3 non-randomized controlled trials. Risk of bias via Centre for Reviews and Dissemination criteria.

Children with acute gastroenteritis. Enterogermina® (B. clausii O/C, N/R, SIN, T) vs ORT ± zinc. Multiple country populations.

SOLID EVIDENCE that Enterogermina shortened DURATION OF DIARRHEA + REDUCED NUMBER OF STOOLS + SHORTENED DURATION OF HOSPITAL STAY vs ORT. Less robust evidence: stool consistency, vomiting, fever. Foundational meta-analytic evidence — most rigorous probiotic evidence base for pediatric acute gastroenteritis. Industry-related context (Sanofi-related Enterogermina product).

2
PMC7680487 — Enterogermina H. pylori Eradication 130-pt RCT
PubMed

Randomized double-blind single-center phase IIIB study (PMC7680487, Infect Dis Ther 2020).

130 adult outpatients with H. pylori infection in Italy. 1 Enterogermina® capsule (2×10^9 spores) or placebo 3 times daily for 2 weeks. Concurrent clarithromycin 500 mg + amoxicillin 1 g + rabeprazole 20 mg twice daily eradication therapy.

WEEK-1 DIARRHEA INCIDENCE 29% in B. clausii group vs 48% in placebo group (RR 0.61, 95% CI 0.39-0.97, p=0.03). Diarrhea remained lower throughout 2-week treatment. Foundational adult AAD prevention evidence with statistical significance. Sanofi-related industry context.

3
PMC8994895 — Enterogermina India Pediatric Acute Diarrhea Phase 3 RCT
PubMed

Phase 3 randomized double-blind placebo-controlled study (PMC8994895).

Patients aged 6 months to 5 years with acute moderate diarrhea (WHO 2005 definition) <48h duration in India. B. clausii probiotic (Enterogermina® oral suspension 2 billion spores per 5 mL) twice daily for 5 days vs placebo, plus ORT and zinc.

Foundational pediatric Indian-population evidence supporting global use of B. clausii preparation. Important developing-country acute diarrhea population evidence — high disease burden region. Industry-related context.

About this ingredient

About the active ingredient

BACILLUS CLAUSII (strains O/C, N/R, SIN, T) is a SPORE-FORMING BACTERIUM with INTRINSIC POLYANTIBIOTIC RESISTANCE — commercialized globally by SANOFI as ENTEROGERMINA® and in the Philippines as ERCEFLORA. The standard preparation contains 2×10^9 spores per capsule/vial in lyophilized form. Strains O/C, N/R, SIN, T characterize the most-studied preparation; other B. clausii preparations (e.g., PBC429™) have different strain compositions and may not have equivalent clinical evidence. PIVOTAL CLINICAL EVIDENCE: PMC12182463 SYSTEMATIC REVIEW + META-ANALYSIS of 11 RCTs + 3 non-randomized controlled trials in pediatric ACUTE GASTROENTERITIS — solid evidence for SHORTENED diarrhea duration + REDUCED stool number + SHORTENED hospital stay vs ORT ± zinc. PMC7680487 (Infect Dis Ther 2020) — randomized double-blind 130-patient phase IIIB study during H. PYLORI ERADICATION therapy in Italy: week-1 diarrhea incidence 29% B. clausii vs 48% placebo (RR 0.61, 95% CI 0.39-0.97, p=0.03). PMC8994895 — phase 3 RCT in India in 6mo-5yr children with acute moderate diarrhea using ORT + zinc + B. clausii. NCT00447161 PADRE trial — phase 4 Filipino multicenter pediatric AAD prevention. Mdpi 14:439 (2024) SYSTEMATIC REVIEW of AAD prevention. RCT-supported dosing: pediatric AAD 4×10^9/day; adult AAD 6×10^9/day. SAFETY EVIDENCE: 28-day mouse NOAEL >2000 mg/kg (5×10^11 CFU); no body weight, clinical signs, hematological, biochemistry, gross pathology, histopathology changes.

MECHANISMS: INTRINSIC POLYANTIBIOTIC RESISTANCE (DISTINGUISHING — survives concurrent antibiotic dosing); SPORE-FORMING DURABILITY (heat/acid/bile-resistant — survives gastric transit without enteric coating); ANTIMICROBIAL PEPTIDE production (active against C. difficile, etc.); MICROBIOTA RESTORATION during antibiotic-induced dysbiosis; ANTI-INFLAMMATORY effects (reduces pro-inflammatory cytokines); frequency of defecation reduction (mouse castor oil model). EVIDENCE: 4/5 reflects: (1) PMC12182463 PIVOTAL META-ANALYSIS of 11 RCTs in pediatric acute gastroenteritis — methodologically robust + multiple country populations, (2) PMC7680487 STATISTICALLY SIGNIFICANT 130-pt RCT in adult H. pylori AAD prevention with RR 0.61 (95% CI 0.39-0.97, p=0.03), (3) PMC8994895 phase 3 INDIAN pediatric population RCT, (4) NCT00447161 phase 4 FILIPINO pediatric trial, (5) Mdpi 14:439 SYSTEMATIC REVIEW of AAD prevention, (6) WELL-CHARACTERIZED intrinsic polyantibiotic resistance mechanism — DISTINGUISHING advantage among probiotics, (7) SPORE-FORMING durability mechanism, (8) NOAEL >2000 mg/kg toxicology evidence, (9) GLOBAL clinical use record (Italian + Indian + Filipino + Brazilian + global), (10) industry-sponsored evidence (Sanofi-Enterogermina) — important context but methodology consistent across multiple investigators, (11) higher-evidence than typical probiotic supplement due to dedicated multi-country research program + PIVOTAL meta-analysis. SAFETY: Excellent — extensive global clinical record + NOAEL evidence. Best positioned as: (a) PEDIATRIC ACUTE GASTROENTERITIS adjunct (PMC12182463 PIVOTAL meta-analysis evidence), (b) ANTIBIOTIC-ASSOCIATED DIARRHEA PREVENTION concurrent with antibiotic therapy (intrinsic polyantibiotic resistance distinguishing advantage), (c) H. PYLORI ERADICATION therapy adjunct (PMC7680487 evidence — 19% absolute reduction in week-1 diarrhea), (d) ADULT TRAVELERS' DIARRHEA prevention (extensive global use), (e) IMMUNE SUPPORT (gut microbiota restoration mechanism), (f) DAILY long-term use acceptable based on extensive safety record, (g) ENTEROGERMINA® preferred branded preparation (most clinical evidence for O/C, N/R, SIN, T strains), (h) IMMUNOCOMPROMISED: caution (applies to all probiotics — extremely rare bacteremia case reports), (i) PREGNANCY: limited specific data; consult physician, (j) higher-evidence than typical Lactobacillus/Bifidobacterium probiotic supplement due to spore-forming + polyantibiotic-resistant + meta-analysis-supported indication. Honest framing: B. clausii (Enterogermina®) is one of the BEST-CHARACTERIZED PROBIOTICS for ACUTE GASTROENTERITIS + ANTIBIOTIC-ASSOCIATED DIARRHEA — PMC12182463 meta-analysis of 11 pediatric RCTs is methodologically robust evidence base. The intrinsic polyantibiotic resistance is a genuine pharmacological distinguishing advantage allowing concurrent antibiotic + probiotic dosing — most Lactobacillus/Bifidobacterium probiotics are killed by antibiotics. PMC7680487 H. pylori eradication trial provides statistically significant adult AAD prevention evidence. Spore-forming durability eliminates need for refrigeration or enteric coating. Sanofi industry sponsorship warrants caveat but methodology consistent across multi-country investigators. Note: B. clausii O/C, N/R, SIN, T strains specifically — different B. clausii preparations (PBC429™, etc.) may not have equivalent clinical evidence. Reasonable AAD prevention + acute gastroenteritis + H. pylori eradication adjunct based on rigorous meta-analytic evidence — particularly compelling for those starting antibiotic therapy seeking to prevent diarrhea complications.

Side effects and drug interactions

Common Potential side effects

Generally extremely well-tolerated; spore-forming probiotic with extensive safety record.
Mild GI upset (rare, transient).
Bacteremia in immunocompromised individuals (very rare).
Pregnancy/lactation: limited specific data; consult physician.
Long-term safety: NOAEL >2000 mg/kg (5×10^11 CFU) over 28 days in mice + extensive Italian/Philippine clinical use record.
Allergic reactions (rare).
Industry-sponsorship (Sanofi) — important context for evidence interpretation.

Important Drug interactions

Antibiotics: COMPATIBLE — intrinsic polyantibiotic resistance allows concurrent dosing (DISTINGUISHING ADVANTAGE).
Most medications: well-tolerated combination profile.
Immunosuppressants: caution (applies to all probiotics).
Other probiotics: compatible.
Anticoagulants: no interactions documented.
PPIs (proton pump inhibitors): compatible — spore-forming probiotic survives gastric environment regardless of pH.

Frequently asked questions about Bacillus clausii (Enterogermina® / Erceflora)

What is the recommended dosage of Bacillus clausii (Enterogermina® / Erceflora)?

The clinically studied dose for Bacillus clausii (Enterogermina® / Erceflora) is ENTEROGERMINA® STANDARD: 2×10^9 spores per capsule/vial, 2-3 times daily during antibiotic therapy or for diarrhea management. PMC7680487 H. PYLORI TRIAL: 1 capsule (2×10^9 spores) 3× daily for 2 weeks. PMC8994895 INDIA PEDIATRIC: 2 billion spores per 5 mL bottle, twice daily for 5 days. NCT00447161 PADRE FILIPINO: 1×10^9 spores twice daily. ADULT AAD PREVENTION: 6×10^9 spores/day (per systematic review). PEDIATRIC AAD: 4×10^9 spores/day. STANDARD CONSUMER USE: 2-6 ×10^9 spores/day in divided doses. Take preferably AT TIME OF ANTIBIOTIC DOSING (intrinsic antibiotic resistance allows concurrent administration). Onset: AAD prevention immediate (concurrent with antibiotics); GI effects within hours-days. Long-term safety: 28-day mouse NOAEL >2000 mg/kg (5×10^11 CFU); extensive Italian/Philippine clinical use record. Pregnancy/lactation: limited specific data; consult physician.. Always follow product labeling and consult a healthcare provider for personalized dosing recommendations.

What is Bacillus clausii (Enterogermina® / Erceflora) used for?

Bacillus clausii (Enterogermina® / Erceflora) is studied for pediatric acute gastroenteritis 11-rct meta-analysis (pmc12182463), h. pylori eradication therapy diarrhea reduction (pmc7680487 130-pt rct), aad prevention systematic review (mdpi 14:439). PMC12182463 — SYSTEMATIC REVIEW + META-ANALYSIS of 11 RANDOMIZED CONTROLLED TRIALS + 3 non-randomized controlled trials. Population: children with acute gastroenteritis. Intervention: Enterogermina® (B.

Are there side effects from taking Bacillus clausii (Enterogermina® / Erceflora)?

Reported potential side effects may include: Generally extremely well-tolerated; spore-forming probiotic with extensive safety record. Mild GI upset (rare, transient). Always consult a healthcare provider before starting any new supplement, especially if you have underlying conditions or take medications.

Does Bacillus clausii (Enterogermina® / Erceflora) interact with medications?

Known drug interactions may include: Antibiotics: COMPATIBLE — intrinsic polyantibiotic resistance allows concurrent dosing (DISTINGUISHING ADVANTAGE). Most medications: well-tolerated combination profile. Consult a pharmacist or healthcare provider if you take prescription medications.

Is Bacillus clausii (Enterogermina® / Erceflora) good for digestive health?

Yes, Bacillus clausii (Enterogermina® / Erceflora) is researched for Digestive Health support. PMC12182463 — SYSTEMATIC REVIEW + META-ANALYSIS of 11 RANDOMIZED CONTROLLED TRIALS + 3 non-randomized controlled trials. Population: children with acute gastroenteritis. Intervention: Enterogermina® (B. clausii O/C, N/R, SIN, T) vs ORT (Oral Rehydration Therapy) ± zinc.