Current Use of “Healthy” Bacteria (Probiotics) in Allergy (A Narrative Review)

The human microbiome plays a crucial role in immune regulation, and its imbalance is associated with allergic diseases such as atopic dermatitis, allergic rhinitis, and asthma. Probiotics have emerged as a potential strategy for restoring microbial balance and modulating immune responses. This review evaluated 34 studies published between 2010 and 2025, including randomized controlled trials, clinical trials, and systematic reviews, focusing on pediatric populations. The findings indicate that specific probiotic strains can reduce allergic symptoms, decrease Th2 cytokines (IL-4, IL-5, IL-13), increase IFN-γ, improve clinical scores (SCORAD, TNSS, C-ACT), and modulate inflammatory miRNAs. Children showed higher responsiveness, likely due to greater immune plasticity and microbiome development. No serious adverse effects were reported. Although probiotics are not a replacement for conventional therapies, they represent a promising, safe adjunct in the prevention and management of allergic diseases, particularly in children. Further research is needed to define optimal strains, dosages, and treatment protocols.