Effects of Circadian Rhythm and Melatonin on Epilepsy Research

A significant amount of clinical and experimental research has been conducted on the treatment of epilepsy, a condition that negatively impacts human health and quality of life.Circadian rhythm refers to vital physiological changes occurring over an approximately 24-hour period, primarily influenced by daylight.Melatonin levels play a crucial role in this mechanism, with its secretion varying throughout the day.This review aims to assess the potential impact of circadian rhythm-related changes in melatonin levels on epilepsy research findings.The PubMed, Google Scholar, and Web of Science databases were used to search for relevant publications.Articles published up to 2025 were included in the review.Melatonin modulates neuronal electrical activity by reducing glutamatergic transmission and increasing GABAergic neurotransmission.In humans, melatonin has been shown to alleviate seizures and to exert positive effects in the treatment of childhood refractory epilepsy.In addition, it has been found to improve physical, emotional, cognitive, and social functions.A significant portion of experimental studies has confirmed the anticonvulsant properties of melatonin.However, several studies have shown that melatonin exerts direct or indirect proconvulsant effects.This review revealed that epilepsy research data sometimes show contradictory results.The seizure parameters tested in these studies, as well as cognitive and behavioral characteristics, may be influenced by daily variations in circadian rhythms.It was concluded that considering circadian rhythms-related variables during the conduct of these studies and basing all modeling and planning on them is essential.