Effects of Lactic Acid Bacteria in Patients With Attention-Deficit/Hyperactivity Disorder

The study aims to evaluate whether postbiotics supplementation can improve ADHD symptoms, such as mood and sleep, in children. Furthermore, salivary biochemical profiles will be analyzed and dietary habits will be recorded to further explore the effects and mechanisms of action of postbiotics.

Research process: 80 subjects who meet the admission conditions will be recruited within three years after IRB approval. They will take the research capsules (postbiotics) in an open label design study and complete the 8-week intervention plus 4 weeks follow up trial period.

Study Overview

• Status: Enrolling by invitation
• Conditions: ADD/ADHD; ADHD - Attention Deficit Disorder With Hyperactivity
• Intervention / Treatment: Dietary supplement: postbiotics

Detailed Description

In recent years, increasing attention has been directed toward the impact of lifestyle and dietary factors on cognitive function, mood, and sleep. Probiotics are defined as live microorganisms that, when administered in adequate amounts, confer health benefits to the host by modulating gut microbiota composition, intestinal barrier function, inflammatory responses, and antioxidant activity. Through these mechanisms, probiotics may contribute to host health by delaying disease progression, regulating pathological processes, and preventing disease-related complications. A growing body of basic and clinical evidence has further demonstrated associations between the gut microbiota, probiotic interventions, and a range of neuropsychiatric and neurodegenerative conditions, including stress-related disorders, autism spectrum disorder (ASD), anxiety, depression, and Parkinson's disease (PD).

In addition to live probiotics, increasing interest has been directed toward postbiotics, which are defined as preparations of inanimate microorganisms and/or their components that confer health benefits to the host. Postbiotics contain a variety of bioactive constituents, including cell wall components (such as peptidoglycans and lipoteichoic acids), intracellular contents, and microbial metabolites produced during fermentation. These components are known to interact with host immune and metabolic pathways, contributing to immunomodulatory, anti-inflammatory, antioxidant, and gut barrier-enhancing effects. Importantly, postbiotics may exert biological activities similar to those of live probiotics while avoiding several limitations associated with viable microorganisms.

The strain investigated in the present study is heat-treated Lactiplantibacillus plantarum. Although heat treatment abolishes its capacity for replication, the resulting postbiotic retains multiple bioactive components, including intact cell wall structures and postbiotic metabolites. Heat treatment also enhances product stability and shelf life, reduces sensitivity to environmental conditions, and ensures consistent dosing, thereby improving suitability for clinical application. From a safety perspective, postbiotics eliminate the risk of microbial translocation, infection, or horizontal gene transfer, which may be of particular concern in vulnerable populations such as children, the elderly, or individuals with compromised immune function. Consequently, postbiotics are increasingly regarded as a safe and reliable alternative to live probiotics in clinical research and practice.

Heat-treated Lactiplantibacillus plantarum has been investigated in several clinical contexts, including ASD, attention-deficit/hyperactivity disorder (ADHD), and Parkinson's disease, demonstrating potential benefits in modulating neurological and behavioral outcomes. Collectively, these findings support the rationale for further investigation of postbiotic interventions as a stable, safe, and biologically active strategy for targeting gut-brain axis-related conditions

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Taiwan
  • Taiwan
    • Taichung, Taiwan, Taiwan, 404332
      • China Medical University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Age 6-13 years old
2. Has been diagnosed with ADHD and is taking medication regularly or has not yet started medication.

Exclusion Criteria:

1. Have taken antibiotics within one month or are receiving antibiotic treatment
2. Have used probiotic products in powder, capsule or tablet form within one month (including yogurt, yogurt, Yakult and other related foods)
3. Those who are allergic to lactic acid bacteria products
4. Obtain a disability certificate
5. Participating in other human research
6. Determined unsuitable by the investigator

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Postbiotics; Dietary Supplement	Dietary supplement: postbiotics; The participants will consume 2 capsules of postbiotics supplement per day for 8 weeks

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total Scores of Clinical Symptoms-Swanson, Nolan, and Pelham Rating Scale-4th Edition(SNAP-IV)	The SNAP-IV is used assess symptoms of ADHD (Attention Deficit Hyperactivity Disorder) in children and adolescents. It consists of a series of questions that rate the severity of behaviors such as inattention, hyperactivity, and impulsivity, based on teacher and parent observations. The scale includes both parent and teacher versions, allowing for a comprehensive view of a child's behavior in different environments. The scoring system rates each behavior on a 4-point scale from 0 (never or rarely) to 3 (very often), and higher total scores indicate more significant ADHD symptoms. The results help clinicians in diagnosing ADHD and monitoring treatment progress.	Baseline, 8th week and 12th week
Total Scores of Child Behavior Checklist	This parent-reported questionnaire is a comprehensive assessment tool for identifying behavioral and emotional problems in children. It includes 100 items (scored 0-3) covering multiple domains such as anxiety, depression, social issues, and aggressive behavior, providing a detailed profile of the child's psychological functioning. The score ranges from 0-200, with a higher score representing higher concern of behavior problems.	Baseline, 8th week and 12th week
Changes of Sleep and Appetite	Use Fitbit and sleep diary to monitor the bedtime resistance, sleep resistance, sleep disordered breathing, night-waking, daytime sleepiness and sleep onset delay. Diet diary and InBody to monitor the change of appetite and body weight.	Baseline, 8th week and 12th week

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Parenting Stress Index, Fourth Edition Short Form , PSI-4-SF	The PSI-4-SF yields scores on the following subscales: 1) Parental Distress, 2) Parent-Child Dysfunctional Interaction, and 3) Difficult Child. The instrument has 36 items which are responded to on a 5-point scale ranging from Strongly Agree to Strongly Disagree. A Total Stress Score is obtained by combining the subscales. The software to score the PSI-4-SF provides a percentile score. Percentile scores between 16 and 84% are considered normal stress, while scores of 85-89% indicate high stress and scores of 90% or higher indicate stress levels that may be clinically significant.	Baseline and 8th week
Visual Analogue Scale for Gastrointestinal Symptoms, VAS-GI	Visual Analogue Scale for GI symptoms, VAS-GI (visual analogue scale, VAS 0-10) was designed to measure the response of symptoms and well-being.	Baseline and 8th week
Clinical Global Impressions-Severity, CGI-S and Clinical Global Impressions-Improvement, CGI-I	Clinical Global Impression Scale (CGI) severity item provided with a seven-point scale of severity of the patient's clinical condition (1=normal, not at all ill; 2=borderline mentally ill; 3=mildly ill; 4=moderately ill; 5=markedly ill; 6=severely ill; 7=among the most extremely ill patients).	Baseline, 8th week and 12th week
The Patient Global Impression of Change (PGI-C)	The Patient Global Impression of Change (PGI-C) consists of one item taken from the clinical global impression and adapted to the patient. The minimum total score possible is 1 and the maximum total score possible is 7. Higher values represent a worse outcome. We exploratorily investigate participants' subjective impression after intervention by PGI-C. The percentage of participant's response in each category, such as "very much improved", "minimally improved", "no change", or "minimally worse" were used to draw an overall conclusion of the intervention potential in the open-arm trial.	8th week and 12th week
Conners Continuous Performance Test 3rd Edition, Conners CPT 3	Conners' Continuous Performance Test - 3rd Edition (CCPT-3) is a computerized measure of inattentiveness, impulsivity, sustained attention, and vigilance for aged 8 and above. Conners' Kiddie Continuous Performance Test (K-CPT) will be used for children aged 6 and 7 which provides a comparable measure of the four domains of attention. To account for two different measures in analyses, standardized scores will be used.	Baseline and 8th week
Oxidative stress	Oxidative stress, an imbalance between free radicals and antioxidants, is strongly linked to ADHD, contributing to cellular damage, neuroinflammation, and neurotransmitter issues, with studies showing lower antioxidant levels and higher stress markers in individuals with ADHD. Oxidative stress related biomarkers such as Salivary alpha-amylase, sAA, Catalase , CAT, Total antioxidant capacity , TAC, Melatonin, Cortisol will be tested.	Baseline and 8th week

Collaborators and Investigators

• Sponsor: I-Ching Chou
• Collaborators: Bened Biomedical Co., Ltd.

Study record dates

Study Major Dates

• Study Start (Actual): February 25, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2028

Study Registration Dates

• First Submitted: January 23, 2026
• First Submitted That Met QC Criteria: February 12, 2026
• First Posted (Actual): February 19, 2026

Study Record Updates

• Last Update Posted (Actual): February 27, 2026
• Last Update Submitted That Met QC Criteria: February 24, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: ADHD; food supplements; ADD
• Additional Relevant MeSH Terms: Mental Disorders; Neurodevelopmental Disorders; Attention Deficit and Disruptive Behavior Disorders; Attention Deficit Disorder with Hyperactivity
• Other Study ID Numbers: CMUH114-REC3-212

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No