The patient is an 18-y-old white woman who presents for evaluation of excessive daytime sleepiness, with long sleep time, and an Epworth Sleepiness Scale score of 19/24. Her past medical history is significant for depression, anxiety disorder with panic attacks, and suicidal ideation, and intent, without plan, requiring psychiatric and psychological counseling.She goes to bed at 21:00, falls asleep within minutes, does not awaken during the night, and rises in the morning at 07:30 with multiple alarms, often not feeling refreshed, and sometimes sleeps through multiple alarms missing school. She denies snoring, apnea, lower extremity restlessness, cataplexy, hypnogogic/hypnopompic hallucinations, or typical sleep paralysis, but does report a single episode where she tried to awaken in the morning but was not able to move for over 30 min.Medications include paroxetine, and over-the-counter iron and carnitine supplements, which have not resolved her daytime sleepiness. She denies use of tobacco, alcohol, or illicit drugs; and drinks caffeine beverages only occasionally. Body mass index is 20.4 kg/m 2 , oral airway is not crowded; and remainder of physical and neurological examination is unremarkable.Seven-day wrist actigraphy performed immediately before diagnostic polysomnography showed variability in sleep SLEEP MEDICINE PEARLS