Prospective observational crossover study of 150 consenting adult patients who are undergoing chronic pain management. For insomnia treatment, each patient ingests prescribed doses of Lemborexant or Zopiclone or Clonidine on alternate nights. Each patient uses a special validated sleep diary to collect data including pain score, sleep score, sleep duration, sleep medication type, and adverse effects. Each patient completes the diary for 3 continuous weeks. Pain is measured using the numeric pain rating scale. Sleep score is measured using the Likert sleep scale. A change in the pain or sleep scores by 2-points is considered significant.

Objectives: Chronic pain is usually associated with insomnia. The objective of this clinical study is to compare the safety and efficacy of Lemborexant or Zopiclone or Clonidine; for the management of chronic insomnia in patients with chronic pain.

Methods: Prospective observational crossover study of 150 consenting adult patients who are undergoing chronic pain management. For insomnia treatment, each patient ingests prescribed doses of Lemborexant or Zopiclone or Clonidine on alternate nights. Each patient uses a special validated sleep diary to collect data including pain score, sleep score, sleep duration, sleep medication type, and adverse effects. Each patient completes the diary for 3 continuous weeks. Pain is measured using the numeric pain rating scale. Sleep score is measured using the Likert sleep scale. A change in the pain or sleep scores by 2-points is considered significant. Data analyzed with IBM® SPSS® Statistics 25 (IBM Corp, Armonk, NY); using Student's t-test, ANOVA, Pearson Chi-square test, and regression analysis. P-value <0.05 is considered significant.

Inclusion Criteria:

• adult chronic pain patients
• good treatment compliance
• severe chronic insomnia
• failure of non-pharmacologic sleep therapy
• regular zopiclone therapy for 3 months or more
• regular sleep diary
• regular pain diary
• informed consent for diary review
• consent for clinical record quality assurance review

Exclusion Criteria:

• obstructive sleep apnoea
• body mass index (BMI) ≥40
• organ insufficiency
• cognitive disorder
• inability to provide consent
• major neuropsychiatric disorder
• unreliable diary
• cannabis use
• regular alcohol intake
• stimulant use
• substance abuse
• poor treatment compliance
• high dose opioid
• gabapentinoid use
• sedative use
• mild insomina
• irregular zopiclone intake
• regular zopiclone therapy for less than 3 months
• previous adverse/allergic reactions to clonidine or zopiclone

Adult chronic pain clinic patients who have severe chronic insomnia; and undergoing medication treatment for insomnia.