Narcolepsy

A neurological disorder marked by a sudden recurrent uncontrollable compulsion to sleep. Narcolepsy is often associated with cataplexy (a sudden loss of muscle tone and paralysis of voluntary muscles associated with a strong emotion), sleep paralysis (immobility of the body that occurs in the transition from sleep to wakefulness), what are called hypnagogic hallucinations (pre-sleep dreams) and automatic behaviors (such as doing something "automatically" and not remembering afterwards how one did it). 125,000 Americans are estimated to have narcolepsy. It strikes males and females and all races. Symptoms most commonly appear in a person's teens and early twenties. The disease can vary in severity. Some persons with it have mild sleepiness or rare cataplexy (less than one episode per week). Other persons may have moderate sleepiness or infrequent cataplexy (less than one episode a day). Still other persons with narcolepsy may experience severe sleepiness or have severe cataplexy (with one or more episodes of cataplexy per day). The cause(s) of narcolepsy are unknown. Narcolepsy is characterized by abnormal rapid eye movement (REM) sleep regulation. Recently, a newly discovered brain protein (hypocretin 1) has been noted to be decreased in the spinal fluid of affected patients. Narcolepsy is not a fatal disorder in itself but it can lead to fatalities. For example, a narcoleptic may fall asleep while driving. Narcolepsy is usually treated with a medication to improve alertness and an anti-depressant that helps control cataplexy. The U.S. Food and Drug Administration (FDA) in 1998 approved Provigil (modafinil), a non-amphetamine drug for treating the excessive sleepiness of narcolepsy. Other names for narcolepsy include excessive daytime sleepiness (EDS), hypnolepsy, sleeping disease, paroxysmal sleep, and Gelineau syndrome.

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A sleep disorder that usually appears in young adulthood, consisting of recurring episodes of sleep during the day and often disrupted nocturnal sleep; frequently accompanied by cataplexy, sleep paralysis, and hypnagogic hallucinations; a genetically determined disease. SYN: Gélineau syndrome, paroxysmal sleep. [narco- + G. lepsis, seizure]

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nar·co·lep·sy 'när-kə-.lep-sē n, pl -sies a condition characterized by brief attacks of deep sleep often occurring with cataplexy and hypnagogic hallucinations compare HYPERSOMNIA (2)

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n.

an extreme tendency to fall asleep in quiet surroundings or when engaged in monotonous activities. The patient can be woken easily and is immediately alert. It is often associated with cataplexy, sleep paralysis, and hypnagogic hallucinations. One in 2000 individuals may be affected. It has recently been found that narcolepsy is strongly associated with reduced levels of hypocretin in the cerebrospinal fluid.

• narcoleptic adj. n.

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nar·co·lep·sy (nahrґko-lep″se) [narco- + Gr. lepsis a taking hold, a seizure] [DSM-IV] recurrent, uncontrollable, brief episodes of sleep, often associated with hypnagogic or hypnopompic hallucinations, cataplexy, and sleep paralysis. Called also Gйlineau syndrome and paroxysmal sleep.