Lactobacillus plantarum 299v and Improved Irritable Bowel Syndrome Symptoms

Research synthesisLow evidenceModerate effect3 studies · 3 beneficial · 0 neutral · 0 harmful

Across 3 studies, all reported beneficial effects of Lactobacillus plantarum 299v on IBS symptoms, with effect sizes ranging from moderate to large. The largest study (n=2643, a meta-analysis) showed moderate beneficial effects, while a real-life observational study (n=221) reported large effects. Dosing was sparsely reported but one study used 1×10^10 CFU/day. Evidence is limited to these three studies, making conclusions preliminary.

Effective dose range: 1 × 10^10 CFU/day (based on one study)
Studied populations: patients with IBS

Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. Available evidence is overwhelmingly positive — clinical literature in this area is subject to publication bias (null-result studies are less likely to be published or indexed). Study durations were not consistently reported, limiting assessment of time-to-effect.

Generated May 12, 2026

Doses used in studies

CFU/day: 10 billion (median 10 billion, IQR 10 billion–10 billion) — 1 study

Safety in these studies

Overall tolerabilityReported
Self-assessment identified that long-term treatment with LP299V was tolerated well by 94 % of patients.
from: [Treatment of IBS with Lactobacillus plantarum 299v: Therapeutic success increases with le

3 of 3 papers

Strain-Specific Systematic Review with Meta-Analysis of Probiotics Efficacy in the Treatment of Irritable Bowel Syndrome.
- 2026-02-02
- Review · n = 2,643
- Journal of clinical medicine 15(3)
- - Roman Maslennikov
  - Eva Gosteeva
  - Vera Ananeva
  - Lada Korshunova
  - Anastasya Kravtsowa
  - Elena Poluektova
  - Anatoly Ulyanin
  - Alexey Sigidaev
  - Patimat Kikhasurova
  - Vladimir Ivashkin
- PubMed: 41682832
- DOI: 10.3390/jcm15031152
3 Insights on
- Improved Irritable Bowel Syndrome Symptoms
- High evidence
Meta-analyses did not demonstrate the efficacy of ... or Lactobacillus casei Shirota.
Effect
Neutral
Effect size
Small
Significant
No
[Treatment of IBS with Lactobacillus plantarum 299v: Therapeutic success increases with length of treatment - real-life data of a non-interventional study in Germany].
- 2021-02
- Observational · n = 221
- Zeitschrift fur Gastroenterologie 59(02)
- - Heiner Krammer
  - Martin Storr
  - Ahmed Madisch
  - Julia Riffel
- PubMed: 33556972
- DOI: 10.1055/a-1340-0204
20 Insights on
- Improved Irritable Bowel Syndrome Symptoms
- High evidence
During the 12-week treatment, a significant and continuous reduction of overall symptom score (p < 0.05) was observed... Additionally, quality of life increased significantly... In real life, LP299V significantly alleviates the global symptoms of IBS in patients.
Effect
Beneficial
Effect size
Large
Significant
Yes
Dose
1 capsule/day; 1×10^10 CFU
The role of Lactobacillus plantarum 299v in supporting treatment of selected diseases.
- 2021-01-25
- Review
- Central-European journal of immunology 45(4)
- - Karolina Kaźmierczak-Siedlecka
  - Agnieszka Daca
  - Marcin Folwarski
  - Jacek M Witkowski
  - Ewa Bryl
  - Wojciech Makarewicz
- PubMed: 33613097
- DOI: 10.5114/ceji.2020.101515
11 Insights on
- Improved Irritable Bowel Syndrome Symptoms
- Low evidence
The intake of L. plantarum 299v provides benefits for IBS patients, mainly due to normalization of stool and relief of abdominal pain, which significantly improves the quality of life of IBS patients.
Effect
Beneficial
Effect size
Moderate
Significant
Yes

Lactobacillus plantarum 299v and Improved Irritable Bowel Syndrome Symptoms

Strain-Specific Systematic Review with Meta-Analysis of Probiotics Efficacy in the Treatment of Irritable Bowel Syndrome.

[Treatment of IBS with Lactobacillus plantarum 299v: Therapeutic success increases with length of treatment - real-life data of a non-interventional study in Germany].

The role of Lactobacillus plantarum 299v in supporting treatment of selected diseases.