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Related to narcolepsy: sleep apnea, Sleep disorders


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., amphetaminesamphetamine
, any one of a group of drugs that are powerful central nervous system stimulants. Amphetamines have stimulating effects opposite to the effects of depressants such as alcohol, narcotics, and barbiturates.
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) plus antidepressantsantidepressant,
any of a wide range of drugs used to treat psychic depression. They are given to elevate mood, counter suicidal thoughts, and increase the effectiveness of psychotherapy.
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 for cataplexy, can help to control its symptoms.



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.


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.
References in periodicals archive ?
Furthermore, patient awareness programs conducted by various organizations, such as Narcolepsy Network Inc.
2: For most people, the onset of narcolepsy is between ages 10 and 17.
Persson from the Karolinska Institutet, Stockholm, said that the follow-up of Pandemrix vaccinations in a large registry based study in Sweden confirms an increased risk of narcolepsy in children and adolescents, while also providing reassuring results for a large number of other neurological and immune related diseases.
Effects of oral L-carnitine administration in narcolepsy patients: a randomized, double-blind, cross-over and placebo-controlled trial.
Ministers have admitted a link between Pandremix and narcolepsy.
Narcolepsy comes from two Greek words meaning "benumbing seizure.
A spokesman for Glaxo-SmithKline, which produced the drug, said: "It is crucial we learn more about how narcolepsy is triggered.
The CHMP welcomes the work of academic researchers to understand the biological mechanism for the association between Pandemrix and narcolepsy and has expressed its appreciation to the Finnish research team for making these results available for scrutiny in a timely manner.
One study found that the incidence rate of narcolepsy among children under the age of 17 shot up 17-fold after the vaccinations, while the incidence rate for adults over 20 was unchanged.
The newly conducted British study tested patients between the ages of 4 and 18 with narcolepsy onset after January of 2008.
Narcolepsy is a little-known condition that means the sufferer is subject to excessive sleepiness during the day, whatever the quality of night-time sleep.
It said studies had shown a six to 13-fold increased risk of narcolepsy in children and adolescents vaccinated with Pandemrix.