Kleine–Levin syndrome
a rare disorder, primarily occurring in adolescent males, that is characterized by recurring episodes of excessive drowsiness and sleep (up to 20 hours per day). Symptoms, which may last for days to weeks, include excessive food intake, irritability, disorientation, lack of energy, and hypersensitivity to noise. It is possibly due to a malfunction of the hypothalamus, the part of the brain that governs appetite and sleep. [Willi Kleine, 20th-century German neuropsychiatrist; Max Levin (1901–1974), Russian-born U.S. neurologist]