Photobiomodulation for Reducing Sedative-Hypnotic Use:Clinical Trial of a Light-Therapy Device

Background: Insomnia is a prevalent and growing public health issue, with one in three adults affected globally and one in five Taiwanese adults reporting significant sleep disturbances. Long-term use of sedative-hypnotic medications remains common in Taiwan despite clinical guidelines recommending short-term use only, contributing to adverse outcomes such as impaired sleep architecture, cognitive deficits, and elevated dementia risk. Non-pharmacological interventions-particularly light-based therapies-offer promising alternatives but existing bright-light therapy is limited by melatonin suppression and the need for precise daytime timing. Recent advances in photobiomodulation (PBM) suggest that red and near-infrared light, which do not suppress melatonin, may enhance sleep quality and support glymphatic clearance when applied during sleep. Preliminary findings from our prior NSTC-funded industry-academia project demonstrated that 850-nm PBM applied during sleep improved subjective sleep quality and sleep duration among older adults with insomnia who were not using hypnotics. Building on these results, the present study aims to evaluate whether sleep-period PBM can improve sleep quality, enhance daytime alertness and cognitive function, and reduce sedative-hypnotic medication use among adults with chronic insomnia who regularly use these medications. Methods: The study will employ an 8-week, single-blind, randomized controlled trial with two parallel arms: (1) PBM intervention and (2) inactive sham control. We will develop an engineer-certified wearable PBM prototype integrating near-infrared LEDs. Sixty adults who use sedative-hypnotics ≥4 days per week will be recruited. Participants will be randomized in a 1:1 ratio and instructed to use the assigned device applied at acupoints Ex-HN 22 continuously during the sleep period. Outcomes will be assessed at baseline, week 4, and week 8. Primary outcomes include changes in subjective sleep quality (PSQI), hypnotic use