Assessing the Adjunctive Role of Probiotic Supplementation in Children With Adhd: Findings From a Randomized, Double-Blind Controlled Trial Publisher



Hoghoughi N ; Karbasi Amel A ; Shakibaei F
Source: Journal of Comprehensive Pediatrics Published:2026

Abstract

Background: Attention-deficit/hyperactivity disorder (ADHD) is a neurological disorder characterized by persistent patterns of hyperactivity, impulsive behavior, and difficulty maintaining attention. Stimulant drugs are effective in improving ADHD. Objectives: This study sought to assess the impact of probiotic supplementation on managing symptoms of ADHD in children during the 2023 - 2024 period. Methods: In this randomized double-blind placebo-controlled clinical trial, 168 children aged 6 - 12 years diagnosed with ADHD were recruited from child and adolescent psychiatry centers in Isfahan (2023 - 2024). Participants were randomly assigned to receive either probiotics or a placebo for 8 weeks. Data were collected using the ADHD Rating Scale-IV, the Parent Conners Questionnaire, the Pediatric Quality of Life Inventory (PedsQOL, parent version), the Children’s Depression Inventory (CDI, completed by the child), and the Hamilton Anxiety Rating Scale (HAM-A, completed by the parents). Parenting education sessions were conducted for all participants before the intervention phase. Results: No significant differences were observed between the probiotic and placebo groups regarding ADHD symptoms or in physical, emotional, social, psychological, or educational dimensions (all P > 0.05, indicating a lack of statistically significant between-group differences). Both groups demonstrated significant improvement over time in ADHD symptom scores and quality-of-life measures (P < 0.001 for the time effect within groups), likely reflecting the effects of standard treatment and parental training rather than probiotic supplementation. Therefore, the addition of probiotics did not provide statistically significant benefits compared with placebo across any outcome measure (i.e., there was no evidence of a treatment effect beyond the placebo response). Conclusions: Contrary to expectations, probiotic supplementation did not produce measurable advantages over placebo in improving ADHD symptoms or related psychosocial outcomes. Given that the Hamilton Anxiety Questionnaire only measures parental anxiety rather than comprehensive mental health, future studies should include broader parental psychological assessments. Copyright © 2026, Hoghoughi et al.