Efficacy and Safety of a Probiotic Mixture Containing Bifidobacterium animalis subsp. lactis BLa80 and Lacticaseibacillus rhamnosus LRa05 in Children With Attention‐Deficit/Hyperactivity Disorder

Attention-deficit/hyperactivity disorder (ADHD) is a neuropsychiatric disorder. Emerging evidence suggests that gut microbiota may contribute to ADHD pathogenesis and that microbiota modulation could improve its symptoms. This study evaluated the safety and efficacy of a probiotic mixture containing Bifidobacterium animalis subsp. lactis BLa80 and Lacticaseibacillus rhamnosus LRa05 in children with ADHD. An open-label, single-arm trial enrolled children with ADHD (n = 42) who received daily oral probiotics (5 × 10⁹ CFU) for 8 weeks. BRIEF-II and SNAP-IV scales were administered at baseline, Week 5, and Week 9 to assess changes in symptoms. Probiotic intervention significantly reduced scores in BRIEF-II domains (Global Executive Composite, Behavior Regulation Index, Emotion Regulation Index, and Cognitive Regulation Index) and SNAP-IV subscales (Inattention, Hyperactivity-Impulsivity) at Week 9 (all p < 0.05). One participant experienced mild diarrhea (grade 1, resolved spontaneously). No significant changes in hematological/biochemical parameters were observed. This exploratory study found that the probiotic mixture is safe and may improve ADHD symptoms in children, warranting further controlled trials to validate its efficacy and explore the underlying mechanisms. This study has been registered in a clinical trial registry. Trial Registration: ClinicalTrials.gov identifier: NCT06348121.