Photobiomodulation for Autism Spectrum Disorder in Children and Adolescents: A Scoping Review of Core Symptom Outcomes and Safety

Prakasit  Wannapaschaiyong; Nattha  Ketudat; Sitthiphon  Bunman

doi:10.33192/smj.v78i8.282022

Authors

Prakasit Wannapaschaiyong Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
Nattha Ketudat Department of Pediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
Sitthiphon Bunman Department of Community Medicine and Family Medicine, Faculty of Medicine, Thammasat University, Pathumthani 12120, Thailand

DOI:

https://doi.org/10.33192/smj.v78i8.282022

Keywords:

Photobiomodulation, Autism spectrum disorder, Children, Adolescents, Safety

Abstract

Objective: Photobiomodulation (PBM) has emerged as a potential noninvasive intervention for autism spectrum disorder (ASD), but pediatric evidence remains limited and fragmented. This scoping review aimed to map the current literature on PBM for children and adolescents with ASD, focusing on core symptom outcomes and safety.

Materials and Methods: PubMed/MEDLINE, Scopus, Embase, and the Cochrane Library were searched from inception to February 1, 2026. The searches identified 53 records, comprising 51 database records and 2 records from supplementary searching. After deduplication and screening, 8 reports representing 6 independent cohorts were included.

Results: The included studies involved children and adolescents aged 2 to 17 years, with sample sizes ranging from 21 to 46 participants. PBM modalities included transcranial photobiomodulation, low-level laser therapy, and laser acupuncture, with wavelengths ranging from 635 to 850 nm. Treatment schedules ranged from 8 sessions over 4 weeks to home-based treatment for up to 6 months. The reports described improvement in selected autism-related outcomes. Controlled studies reported greater improvements in autism severity, language, communication, and social interaction outcomes, including a between-group Childhood Autism Rating Scale difference of 7.23 points in one trial. No serious treatment-related adverse events were reported; however, safety monitoring and adverse-event ascertainment were incomplete and inconsistent.

Conclusion: PBM appears promising but remains investigational for children and adolescents with ASD. Further rigorous sham-controlled trials with standardized outcome measures and clearer safety reporting are needed.

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