Lactobacillus rhamnosus HN001 and Reduced Eczema Prevalence

Research synthesisLow evidenceLarge effect3 studies · 1 beneficial · 2 neutral · 0 harmful

Across 3 randomized controlled trials, 1 reported a beneficial large-sized effect of Lactobacillus rhamnosus HN001 on reducing eczema prevalence, while 2 found no significant effect (neutral). The most studied dose was approximately 6 × 10^9 CFU daily, and populations included pregnant and breastfeeding mothers and their infants/children. Evidence base is small (only 3 studies) — conclusions should be considered preliminary.

Effective dose range: 6 × 10^9 CFU/day
Studied populations: pregnant and breastfeeding mothers and their infants; high-risk birth cohort

Caveats: Evidence base is small (only 3 studies) — conclusions should be considered preliminary. Only one study reached statistical significance, and it showed a large effect; the two neutral studies were also well-designed RCTs. The beneficial effect was observed in a high-risk cohort with long-term follow-up (to age 4 years), while maternal-only supplementation showed no benefit.

Generated May 13, 2026

Doses used in studies

CFU/day: 6 billion (median 6 billion, IQR 6 billion–6 billion) — 3 studies

Safety in these studies

Overall tolerabilityReported
This study showed that the protective effect of HN001 against eczema... extended to at least 4 years of age.
from: A protective effect of Lactobacillus rhamnosus HN001 against eczema in the first 2 years o

3 of 3 papersPopulation:

Maternal supplementation alone with Lactobacillus rhamnosus HN001 during pregnancy and breastfeeding does not reduce infant eczema
- 2018-04-06
- RCT
- Pediatric Allergy and Immunology 29(3)
- - K. Wickens
  - C. Barthow
  - E. Mitchell
  - T. Stanley
  - G. Purdie
  - Judy Rowden
  - Janice Kang
  - Fiona Hood
  - L. V. D. van den Elsen
  - Elizabeth E Forbes-Blom
  - I. Franklin
  - Phillipa Barnes
  - P. Fitzharris
  - Robyn M. Maude
  - P. Stone
  - P. Abels
  - R. Murphy
  - J. Crane
- PubMed: 29415330
- DOI: 10.1111/pai.12874
7 Insights on
- Reduced Eczema Prevalence
- High evidence
- Rigorous Journal
- Mixed
Maternal-only HN001 supplementation did not significantly reduce the prevalence of eczema
Effect
Neutral
Effect size
Small
Significant
No
Dose
6 × 10^9 colony-forming units daily
Effects of Lactobacillus rhamnosus HN001 in early life on the cumulative prevalence of allergic disease to 11 years
- 2018-11-14
- RCT
- Pediatric Allergy and Immunology 29(8)
- - K. Wickens
  - C. Barthow
  - E. Mitchell
  - Janice Kang
  - N. van Zyl
  - G. Purdie
  - T. Stanley
  - P. Fitzharris
  - R. Murphy
  - J. Crane
- PubMed: 30430649
- DOI: 10.1111/pai.12982
10 Insights on
- Reduced Eczema Prevalence
- High evidence
- Rigorous Journal
- Mixed
HN019 had no significant effect on these outcomes
Effect
Neutral
Effect size
Small
Significant
No
Dose
9 × 10^9 cfu daily from 35-week gestation to 6 months' post-partum in mothers while breastfeeding and from birth to age 2 years in infants
A protective effect of Lactobacillus rhamnosus HN001 against eczema in the first 2 years of life persists to age 4 years
- 2012-06-15
- RCT
- Clinical & Experimental Allergy 42(7)
- - K. Wickens
  - Peter N. Black
  - Thorsten Stanley
  - Edwin A. Mitchell
  - C. Barthow
  - P. Fitzharris
  - Gordon Purdie
  - Julian Crane
- PubMed: 22702506
- DOI: 10.1111/j.1365-2222.2012.03975.x
6 Insights on
- Reduced Eczema Prevalence
- High evidence
- Highly Cited
The cumulative prevalence of eczema by 4 years (Hazard ratio (HR) 0.57 (95% CI 0.39-0.83)) ... were significantly reduced in the children taking HN001
Effect
Beneficial
Effect size
Large
Significant
Yes
Dose
6 × 10(9) cfu/day

Lactobacillus rhamnosus HN001 and Reduced Eczema Prevalence

Maternal supplementation alone with Lactobacillus rhamnosus HN001 during pregnancy and breastfeeding does not reduce infant eczema

Effects of Lactobacillus rhamnosus HN001 in early life on the cumulative prevalence of allergic disease to 11 years

A protective effect of Lactobacillus rhamnosus HN001 against eczema in the first 2 years of life persists to age 4 years