Lactobacillus plantarum
EVIDENCE: WEAKAlso sold as: L. plantarum, L. plantarum 299v, L. plantarum PCS26, N13, Lactiplantibacillus plantarum
L. plantarum is studied mainly for digestion and IBS. One small study in children suggested fewer recurrent UTIs. Direct evidence for bladder control in women is not established.
Compiled by iSupplementReviews editorial team ·Updated 2026-10-10 · 3 sources
- Type
- Probiotic — GI/vaginal species
- Studied dose
- 1–10 billion CFU/day (digestive-health trials); the UTI pilot used ~10⁹ CFU (PCS26) in children
- Best form
- Named strain (299v for IBS, PCS26 for the UTI pilot) — species alone tells you nothing
- Our rating
- WEAK — Mostly small, animal, or traditional evidence
What is Lactobacillus plantarum?
L. plantarum, now classified as Lactiplantibacillus plantarum, occurs in fermented vegetables, sourdough, and the gut. Human research mainly concerns IBS and digestion. It can tolerate acidic conditions, but survival does not establish urinary benefits.
Other names and forms it’s sold as
- 299v: the IBS-studied strain
- PCS26: the strain in the pediatric UTI pilot
- N13 and similar deposit IDs: industrial strains with no published human data
- Multi-strain blends: its usual supplement context
Where does it come from?
Fermented foods (kimchi, sauerkraut, olives, sourdough) and the human digestive tract. It’s among the most acid- and bile-tolerant lactobacilli, which makes it the workhorse of the supplement industry.
How does it work in the body?
Standard probiotic toolkit: lactic-acid production, pathogen exclusion, barrier support, and some documented antimicrobial activity against urinary pathogens in lab work. In the gut it reduces visceral hypersensitivity, the basis of the IBS data.
What is it claimed to do?
Gut health and bloating (the real evidence), immune support, and in urinary formulas, pathogen suppression and microbiome balance.
What does the research show?
| Claim | Evidence | Dose studied | Verdict |
|---|---|---|---|
| IBS bloating/pain | Multiple trials (299v) | ~10¹⁰ CFU/day | Supported |
| UTI recurrence | One pilot — PCS26, children | ~10⁹ CFU | Early/weak |
| Vaginal flora support | Indirect | — | Plausible |
| Bladder leaks / urgency | None | — | Unproven |
The UTI pilot — the whole basis of its urinary reputation
A small pediatric pilot reported preliminary urinary-infection findings for the PCS26 strain. It does not establish benefits for adult women or bladder control.
The PCS26 pilot study (J Clin Med, 2022), notably, the same study FemiCore’s own references cite, followed children receiving the strain for UTI treatment and recurrence, with encouraging preliminary signals. But it’s a small, unblinded pediatric pilot: a hypothesis-generator, not evidence you can bank on. No adult, female, or bladder-control trial exists.
The delivery problem it doesn’t solve
The Wolff et al. trial on oral lactobacilli found the dosed strains never appeared in urine at all; and plantarum, while it can transit the gut, has no demonstrated bladder-colonization pathway. Any urinary benefit would have to work indirectly through vaginal flora, a chain no trial has closed.
What dose was studied?
| Goal | Dose | Form/route | Duration |
|---|---|---|---|
| IBS symptoms | ~10¹⁰ CFU/day (299v) | oral | 4–8 weeks |
| UTI recurrence (pilot) | ~10⁹ CFU (PCS26) | oral, children | weeks |
Side effects
Essentially clean: among the best-tolerated probiotic species. Occasional initial gas/bloating. The standard class caution for severely immunocompromised patients applies.
Drug interactions
- Antibiotics: space dosing or take post-course
- Immunosuppressants: class-level caution for the severely immunocompromised
Who should not take it?
Severely immunocompromised patients. Otherwise safe across populations including children (the PCS26 trial’s own population).
What the authorities say
NCCIH lists lactobacilli as safe with plausible GI benefits. Plantarum specifically holds FDA GRAS status as a food organism and has European food-supplement acceptance: safe everywhere, but its institutional recognition is for GI use, not urogenital.
What to know about Lactobacillus plantarum
L. plantarum has stronger digestive evidence than urinary evidence. A small pediatric UTI pilot does not establish bladder-control benefits in women. Product assessment still requires a named strain and live-bacteria count.
Frequently asked questions about Lactobacillus plantarum
Does Lactobacillus plantarum prevent UTIs?
One small pilot study suggests maybe: the PCS26 strain reduced UTI recurrence in children with a history of UTI. That's a single unblinded pilot in children; no adult or female-specific UTI trials exist. Reasonable hypothesis, minimal evidence.
What is L. plantarum proven for?
Irritable bowel symptoms. Strain 299v has multiple trials showing reduced bloating and abdominal pain. It's one of the most acid-resistant lactobacilli, which is why it survives processing and digestion better than most.
Does L. plantarum colonize the vagina or bladder?
It's a minor, occasional member of the vaginal flora, not a dominant one. Vaginal colonization after oral dosing hasn't been documented for this species, and bladder colonization is unstudied.
Why do bladder formulas include it?
Durability, probably. Plantarum survives capsule manufacturing and stomach acid better than most species. A strain that arrives alive beats one that doesn't, but 'alive in the capsule' is a quality feature, not a clinical effect.
References
Products we reviewed containing Lactobacillus plantarum
Based on recorded labels or seller-described formulas. Inclusion does not establish a match to the strains, preparations or amounts studied here; check each review's disclosure limits.