Biotics for Acne-Prone Skin and Scalp Disorders: A Scoping Review

The scoping review evaluates the effectiveness of biotics—prebiotics, probiotics, synbiotics, postbiotics, and paraprobiotics—in treating acne-prone skin and scalp disorders by modulating the skin microbiome. It includes 66 studies and highlights that multi-strain and synbiotic formulations show strong evidence for reducing inflammation. Notable findings include a synbiotic reducing acne lesions by 56.67% in an 8-week RCT with 114 participants, and oral Lacticaseibacillus paracasei ST11 reducing dandruff by 70% compared to 23% with placebo. Additionally, a mixture of Lacticaseibacillus rhamnosus and Bifidobacterium longum improved alopecia areata by 56% versus 30% in a 24-week study with 26 participants. Despite promising results, challenges such as formulation stability, strain specificity, and regulatory heterogeneity persist, necessitating larger, standardized RCTs with active comparators. The review emphasizes the potential of biotics as adjunctive treatments for acne and scalp disorders, but further research is needed to optimize their use in dermatological applications.