Psychobiotics in pediatric autism spectrum disorder: A systematic review of efficacy, mechanisms, and clinical translation

Table 12 Evidence-based selection of psychobiotic strains and formulations for targeted symptom management in children with autism spectrum disorder

Clinical target	Evidence-based psychobiotic	Key mechanism
Social functioning	Limosilactobacillus reuteri (combined strains)	Oxytocin signaling modulation via the Vagus nerve
Anxiety/mood	Lactiplantibacillus plantarum PS128	Modulation of dopamine and serotonin metabolism
Behavioral irritability	Multi-strain Lacto/Bifido blends	reduction in systemic inflammation/pro-inflammatory cytokines
GI severity	De Simone formulation/Bifidobacterium infantis	Enhancement of intestinal barrier and SCFA production
Global improvement	Fecal microbiota transplantation	Ecosystem-wide restoration of microbial diversity

This table provides a clinical translation of the systematic review findings, mapping specific microbial interventions to their corresponding therapeutic targets within the ASD phenotype. Recommendations are categorized by the primary clinical presentation: (1) Strain specificity: Highlights the transition toward “precision psychobiotics”, where specific strains like Limosilactobacillus reuteri and Lactiplantibacillus. plantarum PS128 are utilized for neurological and emotional modulation rather than general gut health; (2) Clinical metrics: Effects are based on improvements in validated instruments, including the Autism Diagnostic Observation Schedule, Social Responsiveness Scale, Aberrant Behavior Checklist, and the Gastrointestinal Severity Index; and (3) Formulations: Includes single-strain psychobiotics, standardized multi-strain blends (e.g., De Simone Formulation), and ecosystem-wide interventions like Fecal Microbiota Transplantation. These interventions are intended as adjunctive therapies alongside standard behavioral and educational supports. Specific dosing should be adjusted based on individual patient tolerance and clinical response. GI: Gastrointestinal; SCFA: Short-chain fatty acids.