The Role of Biotics in Rosacea: A Narrative Review.

Rosacea is a chronic inflammatory dermatosis affecting the central face of adults, characterized by persistent erythema, flushing, papules, pustules, telangiectasias, and, in some cases, phymatous changes. Its pathogenesis involves a multifactorial interplay of immune dysregulation, neurovascular alterations, genetic predisposition, and disturbances of the skin and gut microbiota. Increasing interest in the gut-skin axis has prompted investigation into microbiota-targeted therapies, including probiotics, prebiotics, postbiotics, and synbiotics. This narrative review evaluates current evidence regarding the role of biotics in rosacea. A literature search was conducted in PubMed/MEDLINE, Scopus, and Web of Science using combinations of the terms "rosacea," "gut-skin axis," "probiotics," "prebiotics," "postbiotics," and "synbiotics." Clinical trials, observational studies, and relevant mechanistic investigations published in English were considered. Available data suggest that certain probiotic strains, administered orally or topically, may improve inflammatory lesions, erythema, and skin barrier function, particularly as adjuncts to standard therapy. However, findings are characterized by significant heterogeneity in strains, dosages, study design, outcome measures, and treatment duration. Evidence supporting the use of prebiotics, postbiotics, and synbiotics in rosacea remains limited and, in many cases, extrapolated from related inflammatory conditions or preclinical models. Although microbiota modulation represents a promising therapeutic avenue, current evidence is insufficient to establish standardized clinical recommendations. Larger, well-designed randomized controlled trials with standardized endpoints and long-term follow-up are required to clarify their efficacy, optimal formulations, and safety.