Probiotics for Eczema: What the Trials Show, by Age

Probiotics for eczema work better as prevention than as treatment. Started in late pregnancy and early infancy, some probiotics, especially Lactobacillus rhamnosus strains, have lowered the number of babies who develop eczema in trials^[1]. For eczema that is already there, the largest review found that probiotics probably make little or no difference to symptoms^[2].

That split matters, because "probiotics for eczema" covers two different questions in the research: preventing eczema in a baby^[3], and treating active eczema in a child or adult^[2]. Below you will find what the trials show for each age group, which strains were tested, what topical skin probiotics are, and the safety points to check first.

Do probiotics help eczema? The answer by age

The honest answer is: a little for prevention in high-risk babies, and inconsistently for treatment. Results depend on who takes the probiotic, when, and which strain.

Probiotics do not replace moisturizers or prescribed treatment. Our eczema and gut health page covers standard eczema care and how the microbiome fits into it.

Can probiotics prevent eczema in babies?

Probiotics given in late pregnancy and early infancy may modestly lower eczema risk, but the certainty is low. The effect is clearest for some Lactobacillus rhamnosus strains.

What the large reviews show

The 2025 Cochrane review pooled 18 trials (3,494 infants) and found a slight reduction in eczema by age 2 (risk ratio 0.87, 95% CI 0.78 to 0.97)^[3]. When the authors kept only the 4 trials at low risk of bias, the effect was no longer clear (risk ratio 0.86, 95% CI 0.69 to 1.07). Probiotics made little or no difference to asthma, hay fever or cow's milk allergy^[3].

Timing may matter. A 2015 systematic review and meta-analysis of 29 trials, done to inform World Allergy Organization guidance, found lower eczema risk at three points of use^[8]:

• by women in the last trimester of pregnancy (risk ratio 0.71);
• by breastfeeding mothers (risk ratio 0.57);
• by infants directly (risk ratio 0.80)^[8].

The certainty of that evidence was rated low or very low^[8]. On that basis, the World Allergy Organization suggests probiotics for pregnant women, breastfeeding women and infants only when the baby is at high risk of allergy, as a conditional recommendation^[4]. The same guideline puts the allergy risk at about 10% for infants without allergic parents or siblings and 20 to 30% for those with an allergic first-degree relative^[4].

The strain matters: two key trials

A Finnish trial gave Lactobacillus rhamnosus GG (LGG) before birth to mothers from families with allergic disease, then to their babies for 6 months^[9]. At age 2, eczema affected 23% of the probiotic group and 46% of the placebo group^[9].

A New Zealand trial of 474 high-risk infants tested two strains side by side, given from 35 weeks of pregnancy and to infants until age 2^[10]. L. rhamnosus HN001 roughly halved the risk of eczema (hazard ratio 0.51), while Bifidobacterium animalis subsp. lactis HN019 had no significant effect (hazard ratio 0.90)^[10].

A 2022 meta-analysis of 11 L. rhamnosus trials found reduced eczema at age 2 or younger (risk ratio 0.60) and at 6 to 7 years (risk ratio 0.62), with high dropout rates tempering the result^[1].

For the newborn side of this question, our guide to probiotics for infant eczema covers strains, forms and safety in the first months of life.

Do probiotics treat eczema in children?

For a child who already has eczema, probiotics may slightly lower severity scores, but the effect is small and inconsistent.

The 2018 Cochrane review included 39 randomized trials of oral Lactobacillus and Bifidobacterium probiotics, mostly in children^[2]. Its main findings:

• Symptoms rated by patients or parents were 0.44 points lower on a 20-point scale, a result consistent with no effect.
• Quality of life did not change.
• Total SCORAD, the standard severity score from 0 to 103, fell by 3.91 points, below the 8.7-point change considered clinically meaningful^[2].

The reviewers concluded that probiotic treatment for eczema is "currently not evidence-based," and that more trials of similar strains may be futile^[2]. The American Academy of Dermatology's patient guidance on childhood eczema also lists probiotics as not found to be effective^[11].

Other reviews are more positive. A meta-analysis of 13 pediatric trials found a 4.5-point SCORAD reduction in children aged 1 to 18 but no effect under age 1. It also found an effect in trials from Asia but none in trials from Europe^[5].

A 2024 European Academy of Allergy and Clinical Immunology (EAACI) task force pooled 20 trials in children without food allergy and reported a significant reduction in SCORAD with probiotics, alone or with prebiotics^[12].

The strongest single result came from a Spanish trial in 50 children aged 4 to 17 with moderate eczema. A daily capsule with three strains cut SCORAD by 19.2 points more than placebo over 12 weeks^[13]. Children on the probiotic also needed topical steroids for flares on fewer days (7.7% vs 10.8% of days). One small trial is not enough to change practice, but it shows why results vary so much between products.

For other childhood uses, see our guide to probiotics for kids.

Do probiotics help eczema in adults?

Adult evidence for this chronic inflammatory skin disease is thin: only 6 of the 39 trials in the Cochrane review enrolled adults, and none older than 55.^[2] Two adult meta-analyses report some benefit.

• A meta-analysis of 6 trials (241 adults) found SCORAD fell by 7.9 points and quality of life improved. Itch severity, skin severity and immune markers did not change significantly, and heterogeneity was very high^[6].
• A network meta-analysis of 9 studies (402 adults) found lower severity in the short and long term. A mix of Lactobacillus salivarius LS01 and Bifidobacterium BR03 ranked highest^[7].

With only 241 and 402 adults in these two analyses^[6][7], a single new trial could shift the results. If you try a probiotic as an adult, treat it as an add-on to your usual care, not a substitute.

What probiotic strains are good for eczema?

No single strain is proven for eczema, and effects differ even between strains of the same species^[10][5]. The table lists the strains with the most direct trial data.

Two patterns stand out. LGG looks useful for prevention but not for treating existing eczema^[9][5]. And a strain that works in one setting may not work in another, as the HN001 and HN019 comparison shows^[10].

The Spanish trial used 1 billion colony-forming units (CFU) a day of its three-strain mix^[13]. The Cochrane reviewers found no standard dose across trials^[2].

ProZema customer reviews vs. the trial evidence

ProZema is a commercial probiotic whose website, retrieved in October 2026, lists B. lactis CECT 8145, B. longum CECT 7347 and L. casei CECT 9104^[14]. That is the same three-strain mix tested in the Spanish trial above^[13].

We did not test the product and do not summarize its customer reviews, which cannot show cause and effect. The published evidence for these strains is one 12-week trial in 50 children aged 4 to 17^[13].

For product picks matched to the strains in the table, see our best probiotics for eczema roundup.

What about topical probiotics for eczema?

Topical probiotics apply live bacteria to the skin instead of the gut, and the early human results are promising but unconfirmed. The best-known example is Roseomonas mucosa, studied by the U.S. National Institute of Allergy and Infectious Diseases (NIAID).

• In an open-label trial of 10 adults and 5 children, R. mucosa taken from healthy volunteers was linked to lower eczema severity, less topical steroid use and less Staphylococcus aureus on the skin, with no adverse events^[15].
• In 15 children under 7, treatment was linked to better barrier function and fewer steroid days. Improvements lasted up to 8 months after treatment stopped^[16].

The 2018 study was open-label, the 2020 report compared results with historical placebo groups, and the researchers called for a placebo-controlled trial^[15][16]. R. mucosa isolates taken from people with eczema worsened outcomes in mouse and cell models, so the specific strain matters^[15]. That is a reason for caution with homemade sprays made from capsule powder, which none of the studies we found tested on eczema skin.

Why would gut bacteria affect eczema?

Eczema involves a weak skin barrier, an overactive immune response and an altered skin microbiome^[15], and early-life gut bacteria may help set how that immune system develops. The evidence linking the two is mostly observational.

In a Swedish study, infants who went on to develop IgE-associated eczema had lower gut microbiota diversity at 1 month of age than infants without allergy^[17]. They also had lower diversity within the genus Bacteroides at that age^[17]. This is the reasoning behind giving probiotics early: the aim is to shape the developing immune system before eczema appears. Reviewers note that definitive evidence on which prevention strategies work still requires large international trials^[18].

For the wider picture, including acne and psoriasis, read our explainer on the gut-skin axis.

Are probiotics safe for children with eczema?

For healthy children, probiotics in trials have mostly caused mild digestive side effects, but some groups need medical advice first.

• Side effects in trials: the Cochrane treatment review found no clear rise in adverse events (risk ratio 1.54, 95% CI 0.90 to 2.63), and the side effects reported were gastrointestinal^[2]. The 2025 infant review reported no serious adverse events^[3].
• Preterm babies: the FDA warned in 2023 that preterm infants given probiotics in hospital are at risk of invasive, potentially fatal infection from the product's own organisms^[19].
• No approved product: the FDA has not approved any probiotic as a drug or biologic for infants of any age^[19].
• Bowel disease: the American Academy of Dermatology notes that some probiotics can worsen Crohn's disease and advises talking with your child's dermatologist first^[11].

Check with a clinician before giving a probiotic to a premature or medically fragile baby, or to anyone with a weakened immune system or serious bowel disease.

How to try a probiotic for eczema sensibly

If you decide to try one, these steps keep the test fair and safe:

1. Keep your current treatment. The Cochrane review judged probiotic treatment for eczema not evidence-based, so treat any probiotic as an add-on at most^[2].
2. Pick a strain with data for your goal. Use the table above: prevention strains and treatment strains are not the same^[5].
3. Give it a set period. Treatment trials ran 4 weeks to 6 months^[2]. The clearest pediatric result was measured at 12 weeks^[13].
4. Track severity the same way each week, such as photos and a 0 to 10 itch score, so you can judge change honestly.
5. Stop if nothing changes after the trial period, and tell your clinician what you tried.

How can you calm eczema naturally?

No supplement has strong evidence. The American Academy of Dermatology reports that probiotics were not found effective for childhood eczema, oil supplements such as evening primrose, borage and fish oil gave inconsistent results, and there is not enough evidence to recommend any vitamin or mineral^[11]. Our eczema and gut health page covers the everyday skin care and treatments that have better support.

For a step-by-step plan that combines skin care, diet and microbiome support, see our eczema and atopic dermatitis protocol.

This article is for general educational purposes and is not medical advice. Probiotic strains, doses and products sold in stores often differ from those used in the studies described. Talk to a qualified healthcare professional before starting a probiotic for yourself or your child, particularly if you are pregnant, your baby was born preterm, or you are immunocompromised, taking prescription medication, or managing a diagnosed condition.