hypersomnia

noun hy·per·som·nia \ ˌhī-pər-ˈsäm-nē-ə \
Updated on: 15 Nov 2017

Definition of hypersomnia

: a disorder of sleep that is characterized by prolonged nocturnal sleep periods which typically occur at least three times a week, by sleep that is not restorative or refreshing, and by the presence of excessive daytime sleepiness
Note: Hypersomnia may occur secondary to a medical condition (such as sleep apnea or depression) or the use of certain medications or may arise spontaneously from an unknown cause.
  • The International Classification of Sleep Disorders defines idiopathic hypersomnia as a disorder of excessive sleepiness that is associated with major sleep episodes, the cause of which is presumed to lie in the central nervous system.
  • —Sudhansu Chokroverty
; also : excessive daytime sleepiness not associated with disturbed nocturnal sleep : hypersomnolence
  • Psychology Today reports that people who persistently fall asleep at their desks may be suffering from the dread hypersomnia
  • —Curt Suplee

First Known Use of hypersomnia

1863


Medical Dictionary

hypersomnia

noun hy·per·som·nia \ -ˈsäm-nē-ə \

medical Definition of hypersomnia

1 : sleep of excessive depth or duration
2 : the condition of sleeping for excessive periods at intervals with intervening periods of normal duration of sleeping and waking — compare narcolepsy

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