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narcolepsy
nar·co·lep·sy N0018000 (när′kə-lĕp′sē)n. pl. nar·co·lep·sies A disorder characterized by sudden and uncontrollable, though often brief, attacks of deep sleep, sometimes accompanied by paralysis and hallucinations. nar′co·lep′tic (-lĕp′tĭk) adj.narcolepsy (ˈnɑːkəˌlɛpsɪ) n (Medicine) pathol a rare condition characterized by sudden and uncontrollable episodes of deep sleep ˌnarcoˈleptic adjnar•co•lep•sy (ˈnɑr kəˌlɛp si) n. a disorder characterized by frequent and uncontrollable attacks of deep sleep. [1875–80; narco- + (epi) lepsy] nar`co•lep′tic, adj., n. narcolepsyPathology. a condition characterized by frequent and uncontrollable lapses into deep sleep. — narcoleptic, adj. — narcolept, n.See also: Sleep a condition characterized by an uncontrollable desire for sleep or sudden onsets of sleep. — narcoleptic, adj.See also: Disease and IllnessThesaurusNoun | 1. | narcolepsy - a sleep disorder characterized by sudden and uncontrollable episodes of deep sleep; "he believes that narcolepsy is attributable to an inability to suppress REM sleep during waking"hypersomnia - an inability to stay awake | Translationsnarcolepsy
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., 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. ..... Click the link for more information. ) 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. ..... Click the link for more information. for cataplexy, can help to control its symptoms. Narcolepsy 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. narcolepsy[′när·kə‚lep·sē] (medicine) 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. narcolepsy
Narcolepsy DefinitionNarcolepsy is a disorder marked by excessive daytime sleepiness, uncontrollable sleep attacks, and cataplexy (a sudden loss of muscle tone, usually lasting up to half an hour).DescriptionNarcolepsy is the second-leading cause of excessive daytime sleepiness (after obstructive sleep apnea). Persistent sleepiness and sleep attacks are the hallmarks of this condition. The sleepiness has been compared to the feeling of trying to stay awake after not sleeping for two or three days.People with narcolepsy fall asleep suddenly—anywhere, at any time, maybe even in the middle of a conversation. These sleep attacks can last from a few seconds to more than an hour. Depending on where they occur, they may be mildly inconvenient or even dangerous to the individual. Some people continue to function outwardly during the sleep episodes, such as talking or putting things away. But when they wake up, they have no memory of the event.Narcolepsy is related to the deep, dreaming part of sleep known as rapid eye movement (REM) sleep. Normally when people fall asleep, they experience 90 minutes of non-REM sleep, which is then followed by REM sleep. People with narcolepsy, however, enter REM sleep immediately. In addition, REM sleep occurs inappropriately throughout the day.There has been debate over the incidence of narcolepsy. It is thought to affect between one in every 1,000 to 2,000 Americans. The known prevalence in other countries varies, from one in 600 in Japan to one in 500,000 in Israel. Reasons for these differences are not clear.Causes and symptomsIn 1999 researchers identified the gene that causes narcolepsy. The gene allows cells in the hypothalamus (the part of the brain that regulates sleep behavior) to receive messages from other cells. When this gene is abnormal, cells cannot communicate properly, and abnormal sleeping patterns develop.The disorder sometimes runs in families, but most people with narcolepsy have no relatives with the disorder. Researchers believe that the inheritance of narcolepsy is similar to that of heart disease. In heart disease, several genes play a role in being susceptible to the disorder, but it usually does not develop without an environmental trigger of some sort.While the symptoms of narcolepsy usually appear during the teens or 20s, the disease may not be diagnosed for many years. Most often, the first symptom is an overwhelming feeling of fatigue. After several months or years, cataplexy and other symptoms appear.Cataplexy is the most dramatic symptom of narcolepsy. It affects 75% of people with the disorder. During attacks, the knees buckle and the neck muscles go slack. In extreme cases, the person may become paralyzed and fall to the floor. This loss of muscle tone is temporary, lasting from a few seconds to half an hour, but frightening. The attacks can occur at any time but are often triggered by strong emotions, such as anger, joy, or surprise.Other symptoms of narcolepsy include:- sleep attacks: short, uncontrollable sleep episodes throughout the day
- sleep paralysis: a frightening inability to move shortly after awakening or dozing off
- auditory or visual hallucinations: intense, sometimes terrifying experiences at the beginning or end of a sleep period
- disturbed nighttime sleep: tossing and turning, nightmares, and frequent awakenings during the night
DiagnosisIf a person experiences both excessive daytime sleepiness and cataplexy, a diagnosis may be made on the patient history alone. Laboratory tests, however, can confirm a diagnosis. These may include an overnight polysomnogram—a test in which sleep is monitored with electrocardiography, video, and respiratory parameters. A Multiple Sleep Latency Test, which measures sleep latency (onset) and how quickly REM sleep occurs, may be used. People who have narcolepsy usually fall asleep in less than five minutes.If a diagnosis is in question, a genetic blood test can reveal the existence of certain substances in people who have a tendency to develop narcolepsy. Positive test results suggest, but do not prove, the existence of narcolepsy.Narcolepsy is a complex disorder, and it is often misdiagnosed. It takes 14 years, on average, for an individual to be correctly diagnosed.TreatmentThere is no cure for narcolepsy. It is not progressive, and it is not fatal, but it is chronic. The symptoms can be managed with medication or lifestyle adjustment. Amphetamine-like stimulant drugs are often prescribed to control drowsiness and sleep attacks. A drug called sodium oxybate (Xyrem) was tested for use in 2004 and was shown to reduce daytime sleepiness as well as cataplexy attacks when used along with stimulants. Patients who do not like taking high doses of stimulants may choose to take smaller doses and "manage" their lifestyles, such as by napping every few hours to relieve daytime sleepiness. Antidepressants are often effective in treating symptoms of abnormal REM sleep.With the recent discovery of the gene that causes narcolepsy, researchers are hopeful that therapies can be designed to relieve the symptoms of the disorder.PrognosisNarcolepsy is not a degenerative disease, and patients do not develop other neurologic symptoms. However, narcolepsy can interfere with a person's ability to work, play, drive, and perform other daily activities. In severe cases, the disorder prevents people from living a normal life, leading to depression and a loss of independence.Key termsCataplexy — A symptom of narcolepsy in which there is a sudden episode of muscle weakness triggered by emotions. The muscle weakness may cause the person's knees to buckle, or the head to drop. In severe cases, the patient may become paralyzed for a few seconds to minutes.Hypnagogic hallucinations — Dream-like auditory or visual hallucinations that occur while falling asleep.Hypothalamus — A part of the forebrain that controls heartbeat, body temperature, thirst, hunger, body temperature and pressure, blood sugar levels, and other functions.Sleep paralysis — An abnormal episode of sleep in which the patient cannot move for a few minutes, usually occurring on falling asleep or waking up. Often found in patients with narcolepsy.ResourcesPeriodicalsSiegel, Jeremy M. "Narcolepsy." Scientific American January 2000.〈http://www.sciam.com/2000/0100issue/0100siegel.html〉."Xyrem Study for EDS in Narcolepsy Shows Positive Data Across All Measures." Pain & Central Nervous System Week January 14, 2004: 69.OrganizationsAmerican Sleep Disorders Association. 1610 14th St. NW, Suite 300, Rochester, MN 55901. (507) 287-6006.Narcolepsy Network. PO Box 42460, Cincinnati, OH 45242. (973) 276-0115.National Center on Sleep Disorders Research. Two Rockledge Centre, 6701 Rockledge Dr., Bethesda, MD 20892. (301) 435-0199.National Sleep Foundation. 1522 K St., NW, Suite 500, Washington, DC 20005. (202) 785-2300. http://www.sleepfoundation.org.Stanford Center for Narcolepsy. 1201 Welch Rd-Rm P-112, Stanford, CA 94305. (415) 725-6517.University of Illinois Center for Narcolepsy Research. 845 S. Damen Ave., Chicago, IL 60612. (312) 996-5176.Other"Stanford Researchers Nab Narcolepsy Gene For SleepDisorders." Stanford University Medical Center. [cited August 5, 1999]. http://www.stanford.edu/%7Edement/ngene.html.narcolepsy [nahr´ko-lep″se] recurrent, uncontrollable, brief episodes of sleep, often associated with hallucinations just beforehand or just afterward, or cataplexy or paralysis" >sleep paralysis. adj., adj narcolep´tic.nar·co·lep·sy (nar'kō-lep-sē), [MIM*161400] 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. Synonym(s): Gélineau syndrome, paroxysmal sleep [narco- + G. lēpsis, seizure] narcolepsy (när′kə-lĕp′sē)n. pl. narcolep·sies A disorder characterized by sudden and uncontrollable, though often brief, attacks of deep sleep, sometimes accompanied by paralysis and hallucinations. nar′co·lep′tic (-lĕp′tĭk) adj.narcolepsy Sleeping sickness Sleep disorders A condition characterized by uncontrollable, recurrent, brief episodes of sleep associated with excess daytime sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations, and often disturbed REM sleep; narcolepsy affects 125,000 US–prevalence 40/105; it is defined as a daytime mean sleep latency of < 5 mins, with verification of REM in 2 of 5 daytime nap periods; narcoleptics may have amnesia for the 'absences,' have fallen asleep while driving or while at work and prefer shift work as 'drowsiness' is more socially acceptable; it may also be accompanied by sleep paralysis Prevalence 1:600–Japan, 1:2400–US, 1:500, 000–Israel, ♂:♀ ratio 1:1, onset age 15– 35; 98-100% of narcoleptics have HLA-DR2 and/or HLA-DQw1 Clinical Narcolepsy tetrad; if accompanied by cataplexy, Pt feels a sense of absolute urgency for sleep in often inappropriate situations–while standing, eating, carrying on conversations, accompanied by blurred vision, diplopia, ptosis Management Pre-planned 'catnaps' throughout day, analeptics–ie, long-term stimulants–eg, methylphenidate, dextroamphetamine or tricyclic antidepressants that inhibit re-uptake of norepinephrine and serotonin; MAOIs may eventually cause tardive dyskinesia. See Insomnia, Narcolepsy tetrad, Sleep apnea syndrome, Sleep disorders. nar·co·lep·sy (nahr'kō-lep-sē) 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. Synonym(s): Gélineau syndrome. narcolepsy A disorder featuring an overwhelming tendency to fall asleep when relaxing or free from stimulating demands. People with narcolepsy may drop off many times a day and sleep for minutes to hours. The cause is unknown. Driving a car may be dangerous.Gélineau, Jean Baptiste Edouard, French physician, 1859-1906. Gélineau disease - Synonym(s): Gélineau syndromeGélineau-Redlich syndrome - Synonym(s): Gélineau syndromeGélineau syndrome - a sleep disorder that usually appears in young adulthood. Synonym(s): Gélineau disease; Gélineau-Redlich syndrome; narcolepsynar·co·lep·sy (nahr'kō-lep-sē) [MIM*161400] Sleep disorder, mostly in young adults, with recurring diurnal episodes of sleep and often disrupted nocturnal sleep. Patient discussion about narcolepsyQ. How do you wake up in the morning if your narcolepsy is so severe you can't hear the alarm clock, phone ring? biggest problem is sleep paralysis, can't wake up. Late for work, everything, life is suffering because of severity. Have tried ritalin, natural supplements, hypnosis therapy, Provigal, antidepressants, nothing seems to work. Employer thinks it's an excuse, friends are irritated, I'm at my wits end. Life is spent sleeping more than awake.A. Narcolepsy cannot yet be cured. But EDS and cataplexy, the most disabling symptoms of the disorder, can be controlled in most patients with drug treatment. Often the treatment regimen is modified as symptoms change. For decades, doctors have used central nervous system stimulants-amphetamines such as methylphenidate, dextroamphetamine, methamphetamine, and pemoline-to alleviate EDS and reduce the incidence of sleep attacks. For most patients these medications are generally quite effective at reducing daytime drowsiness and improving levels of alertness. However, they are associated with a wide array of undesirable side effects so their use must be carefully monitored. Common side effects include irritability and nervousness, shakiness, disturbances in heart rhythm, stomach upset, nighttime sleep disruption, and anorexia. For full article: http://www.ninds.nih.gov/disorders/narcolepsy/detail_narcolepsy.htm#120393201 Hope this helps. More discussions about narcolepsynarcolepsy Related to narcolepsy: sleep apnea, Sleep disordersWords related to narcolepsynoun a sleep disorder characterized by sudden and uncontrollable episodes of deep sleepRelated Words |