Description: Pain that lasts longer than the expected period of healing is tormenting a significant percentage of the population and is the leading cause of disability worldwide. Although medications are available to control it, its management often involves trial and error, especially in cases where specific nerve damage cannot be found. Professor Albert Dahan at the Leiden University Medical Center in the Netherlands is studying a controversial and often overlooked drug called ketamine, including its role in pain management and mood disorders, but also in regulating heart function and breathing.