Objective: Topical probiotics have been used for skin care and treatment since the early 20th century. Over the past decade, there has been a dramatic surge of commercially-available topical probiotic products. We conducted a systematic search of clinical data relating to the use of topical probiotics and identified relevant clinical and regulatory gaps. Methods: PubMed and Google Scholar searches were conducted for trials and reviews of probiotics. FDA definitions of cosmetics, drugs, and regulation of topical probiotics were reviewed. Results: Topical probiotics have shown efficacy in a number of limited trials, particularly those involving the treatment of acne, atopic dermatitis, and rosacea. However, there is a paucity of literature on the safety profiles, mechanistic action, and therapeutic potential of topical probiotic products. Several regulatory gaps exist, including approval and classification of topical probiotic products by the FDA; currently there are no topical probiotic products the FDA has approved as drugs. Conclusion: With increasing popularity among the general public, but insufficient clinical data to demonstrate large-scale effectiveness and a thorough understanding of side effects, there is a need for further mechanistic and clinical investigation, as well as improved regulation and standardization of topical probiotic products.
