GAL and sleep disorder: Lastly, four studies exploring adenosine and glycine were inconclusive of the exo-MLT effect, while we could not find any data on histamine and galanin.<h4>Discussion</h4>This review underscores exo-MLT's mechanisms beyond circadian regulation, offering therapeutic promise in sleep disorders associated with other neuropsychiatric conditions.<h4>Conclusion</h4>Exo-MLT's interactions provide insights into its safety and non-addictive characteristics, supporting its integration into personalized sleep medicine.