In children presenting to the paediatric emergency department (PED) with acute gastroenteritis, does the use of probiotics lead to a shorter duration of diarrhoeal symptoms?
Date First Published:
March 27, 2026
Last Updated:
March 27, 2026
Report by:
Dr Megan Littlewood, Junior Locally Employed Doctor/SHO (Royal Manchester Children's Hospital)
Search checked by:
Dr Edward Showler, Senior House Officer
Three-Part Question:
In (children presenting to PED with acute gastroenteritis} does [the administration of probiotics) [reduce duration of diarrhoeal symptoms]?
Clinical Scenario:
An 18-month-old with a two-day history of diarrhoea and vomiting is diagnosed with viral gastroenteritis. They are tolerating oral fluids and you feel they are safe to discharge. Their parents ask if probiotics could help with the diarrhoea. You wonder whether evidence supports probiotics in reducing diarrhoea duration in children with acute gastroenteritis managed in the paediatric emergency department (PED).
Search Strategy:
A search was conducted using Ovid to access EMBASE and MEDLINE databases from 1946 to May 2025. The references of relevant articles were screened, and Google Scholar was used to identify additional studies citing the relevant papers. A supplementary search of the Cochrane Database was performed using the following terms: [gastroenteritis] AND [child OR paediatric OR adolescent] AND [probiotic].
Search Details:
[[adenovirus gastroenteritis/ or acute gastroenteritis/ or viral gastroenteritis/ or gastroenteritis.mp. or gastroenteritis/ or Transmissible gastroenteritis virus/] AND [paediatric.mp. or exp pediatrics/]] OR [infantile gastroenteritis/] AND [probiotics.mp. or exp probiotic agent/]
Outcome:
We excluded studies not conducted on children in any setting other than PED (e.g. hospitalised, primary care, outpatients).
The initial search identified 90 papers following the removal of 21 duplicates. 87 were excluded after title and abstract screening. A further 16 studies were identified through reference list screening and five were identified using the ‘cited by’ function on google scholar, no relevant papers were identified through Cochrane search. Of the 24 papers remaining, 19 were excluded after full text review because they were not conducted in PED setting (n=12), conference paper (n=1), not relevant to our three-part question (n=2) or due to being a secondary analysis of two included RCT’s (n=4). A total of 5 RCT’s met our inclusion criteria. The results are summarised in Table 1.
The initial search identified 90 papers following the removal of 21 duplicates. 87 were excluded after title and abstract screening. A further 16 studies were identified through reference list screening and five were identified using the ‘cited by’ function on google scholar, no relevant papers were identified through Cochrane search. Of the 24 papers remaining, 19 were excluded after full text review because they were not conducted in PED setting (n=12), conference paper (n=1), not relevant to our three-part question (n=2) or due to being a secondary analysis of two included RCT’s (n=4). A total of 5 RCT’s met our inclusion criteria. The results are summarised in Table 1.
Relevant Paper(s):
| Study Title | Patient Group | Study type (level of evidence) | Outcomes | Key results | Study Weaknesses |
|---|---|---|---|---|---|
| Evaluation of treatment in acute gastroenteritis: A comparative study Yalcin et al [1] 2022 Turkey | N= 132, 59.8% male Mean Age: 27.5 months (+/- 3.6 months) Age range: 6months- 6 years Inclusion Criteria: 3 or more loose/watery stools in last 24 hours, diarrhoeal symptoms for <24 hours. Group 1: Dietary recommendations Group 2: Single probiotic (Bifidobacterium breve, bifodobacterium bifidum, bifodobacerium infantis + Bifidobacterium longus strains) Group 3: Zinc Group 4: Probiotics + Zinc. | Single-centre, double-blind, placebo-controlled trial, four arms (Level 2b) | Primary outcome: | Group 4: 43.5 +/- 9.6 hours (range 46-48 hours), (p<0.001) | Small sample size, single-centre study, single probiotic strain studied limiting generalisability. Large exclusion criteria including children with severe symptoms, chronic illness and if other healthcare use had been sought in the same illness. No baseline data on duration of diarrhoea at the start of the trial (large inclusion >24 hours-<2-weeks). |
| Duration of diarrhoea | |||||
| Multicenter Trial of a Combination Probiotic for Children with Gastroenteritis (PROGUT/PECARN trial) Freedman, S.B., Williamson-Urquhart, S., Farion, K.J., Gouin, S., Willan, A.R., Poonai et al. 2018 Canada | N= 886 Median Age: 16 months (probiotic group), 15 months (placebo group) Age range: 3- 48 months Inclusion Criteria: 3 or more loose/watery stools in the last 24 hours (maximum <72 hours) Group 1: 5-day course of a combined probiotic (Lactobacillus rhamnosus R0011 + L. helveticus R0052, 4.0 × 10⁹ CFU twice daily) Group 2: Placebo | Multi-centre (n=6) randomised, double-blind, placebo-controlled trial (Level 1b) | Primary outcome: Moderate to severe gastroenteritis (defined by Vesikari scale) at 14 days post enrolment (classified as a score of >9) | Modified Vesikari Score of >9, probiotic 26.1 vs placebo 24.7, OR 1.06 (0.77-1.46). | Potential for recall bias in Vesikari outcome measure. Inclusion allowed up to 72 hours of symptoms before first dose, may reduce observed effect. |
| Secondary outcome: Duration of diarrhoea | |||||
| Probiotic arm: 52.5 hours [interquartile range, 18.3-95.8] vs placebo arm: 55.5 hours [interquartile range 20.2-102.3], p= 0.31. | |||||
| The Effect of Lactobacillus GG on Acute Diarrheal Illness in the Pediatric Emergency Department Nixon, A.F., Cunningham, S.J., Cohen, H.W. and Crain, E.F. 2012 USA | N= 129, 53% male. Mean age: 25.5 Age range: 6-months to 6-years. Inclusion Criteria: 3 or more loose/watery stools in the last 48 hours. Group 1: LGG powder twice daily for 5-days. Group 2: Placebo Separate sub-group analysis for children who presented with >2 days of symptoms | Single-centre, double-blind, randomised controlled trial (Level 1b) | Primary outcome: Duration of diarrhoea | (LGG 60 hours [37-111 hours) vs placebo 74 hours (43-120 hours), p=0.37) | Placebo is a prebiotic, may limit conclusions based on its use as a comparator. Risk of overinterpretation of sub-group outcome, no description of group size or characteristics. Loss to follow-up of 16.8%, intention to treat analysis not described, potential for attrition bias. |
| Sub-group analysis: | |||||
| (LGG group 51 hours (32-78) vs placebo 74 hours (45-120), p=0.02) | |||||
| Lactobacillus rhamnosus GG versus Placebo for Acute Gastroenteritis in Children (PECARN trial) Schnadower, D., Tarr, P.I., Casper, T.C., Gorelick, M.H., Dean, J.M., O’Connell, K.J et al. 2018 USA | N= 943, 52.9% Median age: 1.4 years (0.9-2.3 years). Age range: 3-months to 4-years of age Inclusion Criteria: 3 or more loose/watery stools per day for <7 days. Group 1: Lactobacillus rhamnosus GG at a dose of 1 x 1010 colony forming units twice daily for 5-days. Group 2: Placebo | Multicentre (n=10) , randomised, double-blind trial (Level 1b) | Primary outcome: Presence of moderate to severe gastroenteritis (classified as a Vesikari score of 9 or more) at Day 5, Day 14 and 1-month post enrolment. | Modified Vesikari score was 9 or higher in 11.8% in the LGG group and in 12.6% in the placebo group (RR, 0.96, 95% CI 0.68 to 1.35, p=0.83) | Potential for recall bias in Vesikari outcome measure. Majority of children had mild disease at inclusion (median baseline Vesikari of 7), harder to detect benefits. Large exclusion criteria. |
| Secondary outcomes: Frequency and duration of diarrhoea. | |||||
| LGG group 49.7 median (18.8-86.4) vs placebo 50.9 median (25.0-88.2), p=0.26 | |||||
| Emergency Department Treatment of Children With Diarrhea Who Attend Day Care. 5. Freedman, S.B., Sherman, P.M., Willan, A., Johnson, D., Gouin, S. and Schuh, S 2015 Canada | N= 123, male 57% Mean age: placebo 23.0 (+/-8.9 months), probiotic (22.5 +/- 9.9) Age range: 4- 48 months. Inclusion Criteria: 3 or more loose stools in the last 24 hours, no more than 96 hours of diarrhoea and vomiting symptoms. Group 1: Low dose (4 x 109 colony forming units per day) or high-dose (8 x 109) colony forming units per day probiotic (lactobacillus helveticus and lactobacillus rhamnosus) Group 2: Placebo | Multicentre (n=3), double-blind, placebo-controlled trial (Level 1b) | Primary Outcome: Day-care absenteeism. | 61% in Group 1 vs 63% in Group 2, OR 0.89 (95% CI= 0.44 to 1.8) | Small sample size. conclusions may be underpowered. Strict exclusion criteria and only including children that attended day-care, limiting generalisability. |
| NSD in diarrhoea duration for low and high dose p= 0.39, and low dose only p=0.27. | |||||
| Secondary outcomes: Unscheduled visit to a healthcare provider, subsequent hospital visit requiring IV fluids, duration of diarrhoea and vomiting, number of days of day care and work absenteeism. |
Author Commentary:
Probiotics are theorised to have several mechanisms of action when used in the treatment of gastroenteritis. These include causing immunomodulatory changes that facilitate the transport of antigens and increase the number of immunoglobulin secreting cells throughout the intestinal mucosa. They are also proposed to produce antibacterial substances, competitively inhibit the adhesion of pathogens to the intestinal mucosa and colonize the intestine with beneficial bacteria alongside creating a ‘hostile’ environment for pathogens [6].
This review found five relevant RCT’s of mixed quality; none of them demonstrated a statistically significant benefit of probiotic therapy [1][2][3][4][5]. One smaller study suggested some synergistic effect of probiotics with zinc. However methodological limitations including small sample size, limited baseline data, and unclear randomisation reduce confidence in this finding [1].
The current NICE guidelines do not support the use of probiotics as part of standard therapy for acute gastroenteritis in children under five [7]. The findings of this review support this position with particular relevance to children treated and managed within PED.
The conclusion from this review falls in line with recent evidence that demonstrates limited benefit of medical therapies for paediatric gastroenteritis following discharge from PED, such as the use of ondansetron and the use of ORS over dilute apple juice [8][9].
This review found five relevant RCT’s of mixed quality; none of them demonstrated a statistically significant benefit of probiotic therapy [1][2][3][4][5]. One smaller study suggested some synergistic effect of probiotics with zinc. However methodological limitations including small sample size, limited baseline data, and unclear randomisation reduce confidence in this finding [1].
The current NICE guidelines do not support the use of probiotics as part of standard therapy for acute gastroenteritis in children under five [7]. The findings of this review support this position with particular relevance to children treated and managed within PED.
The conclusion from this review falls in line with recent evidence that demonstrates limited benefit of medical therapies for paediatric gastroenteritis following discharge from PED, such as the use of ondansetron and the use of ORS over dilute apple juice [8][9].
Bottom Line:
Probiotics should not be routinely prescribed to paediatric patients presenting to PED with acute gastroenteritis.
Level of Evidence:
Level 1: Recent well-done systematic review was considered or a study of high quality is available
References:
- Yalcin et al [1]. Evaluation of treatment in acute gastroenteritis: A comparative study
- Freedman, S.B., Williamson-Urquhart, S., Farion, K.J., Gouin, S., Willan, A.R., Poonai et al.. Multicenter Trial of a Combination Probiotic for Children with Gastroenteritis (PROGUT/PECARN trial)
- Nixon, A.F., Cunningham, S.J., Cohen, H.W. and Crain, E.F.. The Effect of Lactobacillus GG on Acute Diarrheal Illness in the Pediatric Emergency Department
- Schnadower, D., Tarr, P.I., Casper, T.C., Gorelick, M.H., Dean, J.M., O’Connell, K.J et al.. Lactobacillus rhamnosus GG versus Placebo for Acute Gastroenteritis in Children (PECARN trial)
- 5. Freedman, S.B., Sherman, P.M., Willan, A., Johnson, D., Gouin, S. and Schuh, S. Emergency Department Treatment of Children With Diarrhea Who Attend Day Care.