Circadian Rhythms and Pain: A Narrative Review on Clock Genes and Circadian-Based Interventions.

Pain is a common symptom of many diseases and seriously affects the quality of life. Circadian rhythm is the regular, cyclical physiological, biochemical, and behavioral changes that occur within a 24-hour period in biological organisms, primarily regulated by clock genes. Pain sensitivity may have circadian rhythms, with clock genes likely influencing this pain-related rhythmicity. Therefore, restoring normal circadian rhythms and regulating the expression of clock genes are regarded as viable strategies to combat the development of pain. First, this review elucidates the core operational mechanisms of clock genes. Second, it also discusses the relationship among multiple types of pain and clock genes, such as sciatic nerve injury, inflammatory pain, chemotherapy-induced neuropathic pain, headache, the pain of Restless Legs Syndrome and fibromyalgia. Third, it presents the pain treatment and pain management strategies based on the current research on circadian rhythms. Exploring the role of circadian rhythm in pain can help increase our understanding of pain and have significant clinical implications for pain patients.