Also found in: Dictionary, Thesaurus, Medical, Wikipedia.
Related to narcolepsy: sleep apnea, Sleep disorders


narcolepsy, a sleep disorder characterized by excessive daytime sleepiness and recurring unwanted episodes of sleep (“sleep attacks”). People with narcolepsy may abruptly fall asleep at almost any time, including while talking, eating, or even walking. The attacks may range from embarrassing or inconvenient to severely disabling, interfering with a person's daily life. An estimated 125,000–250,000 people in the United States have narcolepsy; it occurs about equally in males and females.

Most people with narcolepsy also experience cataplexy, sudden muscular weakness without loss of consciousness, which usually accompanies laughter or anger. Other symptoms, occurring just after falling asleep or upon awakening, include sleep paralysis (a feeling that one cannot move) and vivid hallucinations.

The cause of narcolepsy is not known with certainty, but most people with narcolepsy have low levels of orexin (or hypocretin), a neurotransmitter that promotes wakefulness. In the case of people with narcolepsy and cataplexy, the cause appears to be an autoimmune response that attacks the brain's orexin-producing neurons. There is no cure. Treatment, including regular planned naps and the use of stimulant drugs (e.g., amphetamines) plus antidepressants for cataplexy, can help to control its symptoms.

The Columbia Electronic Encyclopedia™ Copyright © 2022, Columbia University Press. Licensed from Columbia University Press. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a disease the main symptom of which is an uncontrollable desire for sleep. Narcolepsy can develop after infections (epidemic encephalitis and malaria, for example) or head injuries; it may also be caused by certain brain tumors. Sometimes no apparent cause can be discovered, as in congenital, or genuine, narcolepsy. In addition to being characterized by an uncontrollable desire for sleep, narcolepsy is characterized by cataplectic attacks (loss of muscle tone brought about by exaggerated emotion) and by sudden arousals from nocturnal sleep with a loss of muscle tone. The duration of narcoleptic attacks is brief—from one to 30 minutes. The course of narcolepsy is chronic, but the intensity diminishes with age. Treatment involves both the elimination of the underlying cause and the use of pharmacotherapeutic techniques.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


A disorder of sleep mechanism characterized by two or more of four distinct symptoms: uncontrollable periods of daytime drowsiness, cataleptic attacks of muscular weakness, sleep paralysis, and vivid nocturnal or hypnogogic hallucinations.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
The global Narcolepsy Therapeutics Market is anticipated to witness an exponential growth in the forecast period.
Harmony's chief medical officer, Jeffrey Dayno, MD, said, 'The approval of WAKIX provides healthcare professionals managing people living with narcolepsy a new and important treatment option for their patients.
EDS is the inability to stay awake and alert during the day and is the symptom that is present in all people living with narcolepsy.
Despite this, the mum-of-three felt alone for many years, before discovering the charity, Narcolepsy UK, in 2014.
Solriamfetol is approved at 75 mg and 150 mg for patients with narcolepsy and at 37.5 mg, 75 mg, and 150 mg for patients with obstructive sleep apnea.
But recent trials have shown that it's effective in treating narcolepsy.
After obtaining patients' and parents' consents, three narcolepsy type 1 patients (2 children and 1 adult) were treated within 1 to 4 months after generalized cataplexy onset.
If the urge to sleep is overwhelming and irresistible, it may be a sleep disorder called narcolepsy, a condition affecting approximately one in 2,000 people in the US.
Narcolepsy is a rare disease caused by sleep disorder observed during the rapid eye movement (REM) phase of sleep, which is characterized by excessive sleepiness during daytime accompanied by sudden loss of muscle tonus, hallucinations while falling asleep, and sleep paralysis (1).
Her narcolepsy had led to her sleeping for up to 19 hours per day on occasions and her mental health worsened.
Narcolepsy is a neurological disorder of sleep regulation that affects the control of sleep and wakefulness.
Narcolepsy should not cause serious or long-term health problems but it can have a significant impact on daily life.