Probiotics for Eczema, Food Allergy and Asthma in Children: Prevention and Treatment Trials
What Cochrane reviews and the World Allergy Organization found on probiotics for preventing or treating eczema, food allergy and asthma in children, and why certainty is low.
Content last updated . This page has not been medically reviewed.
Start here: allergy and asthma need a clinician
Allergic reactions and asthma attacks can be emergencies; in the US, call 911. Neither condition should be managed with a supplement alone. A probiotic is not an emergency treatment and does not replace a prescribed inhaler, allergy plan or eczema treatment. NCCIH advises not using probiotics as a reason to postpone seeing a health care provider about any health problem. [1]This page is information only. It does not tell parents to give any product to a child.
Prevention and treatment are different questions
Studies ask two separate things. Prevention trials give a probiotic (to a pregnant woman, a breastfeeding mother, or an infant who does not yet have allergy) and then count who develops eczema or allergy. Treatment trials give a probiotic to children who already have eczema or asthma and measure symptoms. Results for one do not carry over to the other, nor from one strain to another; see why one strain's result does not transfer.What the evidence shows
Labels: promising but limited, mixed, insufficient evidence, no good evidence of benefit. "Low certainty" is the reviewers' GRADE rating.| Question | What the source found | Strength of evidence |
|---|---|---|
| Can probiotics given to infants prevent eczema? | A 2025 Cochrane review (24 studies, 7077 mother-infant pairs) found a slight reduction in eczema by age two (RR 0.87; low certainty), but studies at low risk of bias showed little or no difference. [2] | Mixed |
| Prevent asthma, hay fever or milk allergy? | Same review: probiotics may make little to no difference to asthma, allergic rhinitis and IgE-mediated cow's milk allergy (low certainty). [2] | No good evidence of benefit |
| Prevent food allergy? | Little to no effect, but "very uncertain" (very low certainty). [2] | Insufficient evidence |
| Treat existing eczema? | A 2018 Cochrane review (39 trials, 2599 participants) found probiotics probably make little or no difference to patient-rated symptoms (moderate certainty). [3] | No good evidence of benefit |
| Treat eczema, investigator scores? | A 3.91-point drop on a 0 to 103 severity scale, below the 8.7 points estimated to be clinically important. [3] | Promising but limited, small effect |
| Treat childhood asthma? | A 2025 meta-analysis of eight trials (902 children) found fewer acute asthma episodes with probiotics, but the authors cite heterogeneity and need for studies on strains, amounts and duration. [4] | Mixed |
| What do broader summaries say? | NCCIH describes an earlier asthma review in children as inconclusive and an infant and child eczema review as without consistent benefit. [1] | Mixed |
Why the results are hard to pool. Trials used different strains and combinations, doses and durations, and the 2018 review found significant, unexplained differences between trials. [3] The 2025 review also noted risk-of-bias concerns in most studies. [2]
What guidelines say
- World Allergy Organization (WAO) with McMaster University, 2015: evidence did not indicate that probiotics reduce the risk of developing allergy in children, but the panel saw a likely net benefit mainly from preventing eczema. It conditionally suggested probiotics for pregnant women at high risk of having an allergic child, for breastfeeding women with a high-risk infant, and for high-risk infants, and said all recommendations rest on very low-quality evidence. [5]
- Why this may be out of date: the guideline was written from evidence up to November 2014, before the 2025 Cochrane update above. [5][2]
- EAACI: we searched PubMed for a European Academy of Allergy and Clinical Immunology statement on probiotics for eczema and found none we could read. Proper evidence not found here.
- NHS (UK): says there is no evidence that probiotics can help treat eczema. [6]
Frequently asked questions
Do probiotics prevent eczema in babies?
A 2025 Cochrane review found a slight reduction by age two with low-certainty evidence, but little or no difference in the studies at low risk of bias. [2]
Do probiotics treat eczema?
A 2018 Cochrane review concluded that use of probiotics to treat eczema is not currently evidence-based. [3]
Do probiotics prevent food allergy or asthma?
The 2025 review found little or no difference for asthma and food allergy, with low to very low certainty. [2]
Do probiotics help children who already have asthma?
A 2025 meta-analysis of eight trials reported fewer acute episodes, but results varied and optimal strains and amounts are unknown. [4]
Should a pregnant woman take a probiotic to prevent a child's allergy?
WAO conditionally suggested it for high-risk pregnancies on very low-quality evidence; she should ask her clinician. [5]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety
Pregnancy and breastfeeding: prevention trials gave probiotics to mothers, but a mother should talk with her clinician before using any supplement; see probiotics in pregnancy and breastfeeding and pregnancy and breastfeeding safety. Check medicine interactions with a pharmacist (medication interactions). For the condition itself, see eczema and probiotics for children and teens. Do not stop a prescribed treatment because of anything here.
References
- NCCIH (US National Center for Complementary and Integrative Health). Probiotics: Usefulness and Safety. Page shows "Last Updated: August 2019" with later FDA 2023 content. Read 2026-10-23.
- Wang HZ et al. Cochrane Database Syst Rev 2025. Probiotics in infants for prevention of allergic disease. PMID 40511642. Read 2026-10-23.
- Makrgeorgou A et al. Cochrane Database Syst Rev 2018. Probiotics for treating eczema. PMID 30480774. Read 2026-10-23.
- Liu Y et al. Front Pediatr 2025. Probiotics for children with asthma: a systematic review and meta-analysis. PMID 40342899. Read 2026-10-23.
- Fiocchi A et al. World Allergy Organ J 2015. World Allergy Organization-McMaster University Guidelines for Allergic Disease Prevention (GLAD-P): Probiotics. PMID 25628773. Read 2026-10-23.
- NHS (UK). Probiotics. Read 2026-10-23.