Loddo, G., Calandra-Buonaura, G., Sambati, L., Giannini, G., Cecere, A., Cortelli, P., & Provini, F. (2017). The Treatment of Sleep Disorders in Parkinson's Disease: From Research to Clinical Practice. Frontiers in neurology, 8, 42. https://doi.org/10.3389/fneur.2017.00042; https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5311042
"If insomnia is not iatrogenic and not due to PD (Parkinson's Disease) motor complications, the principal therapy remains the cognitive behavioral therapy.... In the cases in which pharmacological therapy is necessary, eszopiclone, doxepin, zolpidem, trazodone, ramelteon, and melatonin could be useful although these drugs are investigational...." "To avoid tolerance, hypnotic drugs should ideally be used for no longer than 4–5 weeks...." "Melatonin is established as effective in improving patients’ perception of sleep quality, but data are conflicting regarding objective improvement in sleep polysomnographic parameters...."
https://www.sleepfoundation.org/physical-health/parkinsons-disease-and-sleep
https://www.parkinson.org/understanding-parkinsons/non-movement-symptoms/sleep-disorders
https://my.clevelandclinic.org/health/articles/9366-sleep-problems-with-parkinsons-disease
https://www.apdaparkinson.org/what-is-parkinsons/symptoms/sleep-problems/
Measures: Parkinson’s Disease Sleep Scale (PDSS) and its modified version (PDSS-2); Scales for Outcomes in PD-Sleep (SCOPA-S)