Hypersomnia / Excessive Sleepiness Disorder / Idiopathic Hypersomnia

Hypersomnia / Excessive Sleepiness Disorder / Idiopathic Hypersomnia

About Hypersomnia

In Hypersomnia the person feels excessively sleepy despite sleeping for several hours at night. They often require day-time naps.

"Even where sleep is concerned, too much is a bad thing." - Homer

Hyper means 'excessive' and somnia refers to 'sleep', so Hypersomnia is excessively long or deep sleep. Excessive sleepiness is a common symptom, like fever, and can stem from many sleep disorders.

In the fairy tale classic, Sleeping Beauty, a princess pricks her finger with the needle of a spinning wheel and falls asleep for one hundred years. Recently, Taryn Sardis, a seventeen-year-old high school student, experienced a similar experience in 1997. She fell asleep for ten days, and it was impossible to wake her. No spinning wheel was involved, however!! The culprit, in Taryn's case, was a rare disorder called Kleine-Levin Syndrome, which is a type of Hypersomnia.

A hyperomniac may sleep up to twelve hours a night, and still need frequent daytime naps. Besides excessive daytime sleepiness, people with this disorder also tend to oversleep at night but continue to remain sleepy.


As early as 1966, William Dement said that patients who complained of excessive day time sleepiness but did not portray symptoms such as sleep paralysis, cataplexy, or sleep-onset Rapid Eye Movement (REM) should not be categorized as narcoleptics.

In 1972, Roth et al came close to providing an explanation for a certain type of hypersomnia in which the victims were unable to completely wake up from their sleep stupor. They also appeared confused, and were slow and disoriented with poor motor coordination. The typical symptoms exhibited in typical narcolepsy, sudden and unexpected sleep attacks, was not present. The word "hypersomnia" was thus born to describe these typical symptoms.

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