Abstract
Kleine-Levin syndrome is a rare neurological disease of unknown cause beginning typically during adolescence, characterized by remittent-relapsing episodes of severe hypersomnia associated with cognitive and behavioral disturbances. Triggering factors at Kleine-Levin syndrome onset include infection, sleep deprivation, as well as alcohol, drug, and substance intake. A young woman had 6 episodes over 2 years, including hypersomnia, confusion, derealization, cognitive impairment, anxiety, feeling of being scrutinized, anorexia (and sweet craving once) but no hypersexuality. The first episode started after a party where she experienced a complete, 4-hour-long blackout despite moderate alcohol intake. The patient suspected having been poisoned. Twenty-five months after the party, when Kleine-Levin syndrome was eventually diagnosed, her long hair was analyzed and exogenous γ-hydroxybutyrate was found in the tips (corresponding to the party time). This case illustrates the interest of looking for γ-hydroxybutyrate in the hair when Kleine-Levin syndrome starts after a party.