Hypersomnolence Disorder

Traci Speed, M.D., Ph.D., Akachimere Uzosike, David Neubauer, M.D.


  • Hypersomnolence disorder is characterized by repeated excessive sleepiness not attributable to another sleep disorder.
    • In other words, repeated excessive sleepiness despite getting at least seven hours of sleep.
    • Hypersomnolence of central origin signifies an inability to remain awake/alert during periods of wakefulness leading to an irrepressible need to sleep or lapses into sleep during the daytime.[1]
  • Individuals with hypersomnolence and cataplexy are diagnosed with narcolepsy, as are hypersomnolent patients with specific sleep testing results.
  • Hypersomnolence disorder is considered a sleep-wake disorder in DSM-5[2].

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Last updated: May 13, 2022