, under the patronage of the respected President of Al-Qadisiyah University, Dr. Kazem Jabr Al-Jubouri, and the supervision of the respected Dean of the College of Pharmacy, Assistant Professor Dr. Asaad Hassan Al-Zaidi. The seminar titled “Melatonin and its biological effects” was conducted today, Thursday, 25/4/2024, at the Clinical Laboratory Sciences Department, delivered by Assistant Professor Dr. Hussam Hamza Al-Fatlawi. The lecturer discussed the definition of melatonin as a sleep hormone primarily produced by the pineal gland in the brain. Its association with sleep quality was highlighted, as elevated levels aid in promoting sleep by helping the body differentiate night time, linking it to relaxation and rest. The lecture also covered the role of melatonin in regulating the sleep-wake cycle, its antioxidant properties, and its therapeutic applications in various diseases, such as Parkinson’s disease, along with its emerging role as an antiviral agent.