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Narcolepsy What is narcolepsy? Three other classic symptoms of narcolepsy, which may not
occur in all patients, are: Daytime sleepiness, sleep paralysis, and hypnagogic hallucinations
can also occur in people who do not have narcolepsy. In most cases, the first symptom of narcolepsy to appear
is excessive and overwhelming daytime sleepiness. The other symptoms may begin
alone or in combination months or years after the onset of the daytime sleep
attacks. There are wide variations in the development, severity, and order of
appearance of cataplexy, sleep paralysis, and hypnagogic hallucinations in individuals.
Only about 20 to 25 percent of people with narcolepsy experience all four symptoms.
The excessive daytime sleepiness generally persists throughout life, but sleep
paralysis and hypnagogic hallucinations may not. The symptoms of narcolepsy, especially the excessive daytime
sleepiness and cataplexy, often become severe enough to cause serious disruptions
in a person's social, personal, and professional lives and severely limit activities. When should you suspect narcolepsy? How common is narcolepsy? Who gets narcolepsy? What happens in narcolepsy? In narcolepsy, the order and length of NREM and REM sleep
periods are disturbed, with REM sleep occurring at sleep onset instead of after
a period of NREM sleep. Thus, narcolepsy is a disorder in which REM sleep appears
at an abnormal time. Also, some of the aspects of REM sleep that normally occur
only during sleep—lack of muscle tone, sleep paralysis, and vivid dreams—occur
at other times in people with narcolepsy. For example, the lack of muscle tone
can occur during wakefulness in a cataplexy episode. Sleep paralysis and vivid
dreams can occur while falling asleep or waking up. How is narcolepsy diagnosed? Two tests that are commonly used in diagnosing narcolepsy
are the polysomnogram and the multiple sleep latency test. These tests are usually
performed by a sleep specialist. The polysomnogram involves continuous recording
of sleep brain waves and a number of nerve and muscle functions during nighttime
sleep. When tested, people with narcolepsy fall asleep rapidly, enter REM sleep
early, and may awaken often during the night. The polysomnogram also helps to
detect other possible sleep disorders that could cause daytime sleepiness. For the multiple sleep latency test, a person is given
a chance to sleep every 2 hours during normal wake times. Observations are made
of the time taken to reach various stages of sleep. This test measures the degree
of daytime sleepiness and also detects how soon REM sleep begins. Again, people
with narcolepsy fall asleep rapidly and enter REM sleep early. How is narcolepsy treated? In addition to drug therapy, an important part of treatment
is scheduling short naps (10 to 15 minutes) two to three times per day to help
control excessive daytime sleepiness and help the person stay as alert as possible.
Daytime naps are not a replacement for nighttime sleep. Ongoing communication among the physician, the person with
narcolepsy, and family members about the response to treatment is necessary
to achieve and maintain the best control. How can individuals and their families and friends
cope with narcolepsy? Individuals with narcolepsy, their families, friends, and
potential employers should know that: For more information National Heart, Lung, and Blood Institute Information
Center This information was developed by the National Institutes
of Health, National Heart, Lung,
and Blood Institute National Institutes of Health, National Heart, Lung, and
Blood Institute. Facts About Narcolepsy. Available at: http://www.nhlbi.nih.gov/health/public/sleep/narcolep.htm.
Last accessed May 28, 2004. The information in this document is for general educational
purposes only. It is not intended to substitute for personalized professional
advice. Although the information was obtained from sources believed to be reliable,
MedLink Corporation, its representatives, and the providers of the information
do not guarantee its accuracy and disclaim responsibility for adverse consequences
resulting from its use. For further information, consult a physician and the
organization referred to herein.
Copyright© MedLink Corporation 1993-2005 All Rights Reserved
Narcolepsy is a chronic sleep disorder with no known
cause. The main characteristic of narcolepsy is excessive and overwhelming daytime
sleepiness, even after adequate nighttime sleep. A person with narcolepsy is
likely to become drowsy or to fall asleep, often at inappropriate times and
places. Daytime sleep attacks may occur with or without warning and may be irresistible.
These attacks can occur repeatedly in a single day. Drowsiness may persist for
prolonged periods of time. In addition, nighttime sleep may be fragmented with
frequent wakenings.
• Cataplexy: sudden episodes of loss of muscle function, ranging
from slight weakness (such as limpness at the neck or knees, sagging facial
muscles, or inability to speak clearly) to complete body collapse. Attacks may
be triggered by sudden emotional reactions such as laughter, anger, or fear
and may last from a few seconds to several minutes. The person remains conscious
throughout the episode.
• Sleep paralysis: temporary inability to talk or move when falling
asleep or waking up. It may last a few seconds to minutes.
• Hypnagogic hallucinations: vivid, often frightening, dream-like
experiences that occur while dozing or falling asleep.
You should be checked for narcolepsy if:
• you often feel excessively and overwhelmingly sleepy during the day even
after having had a full night's sleep;
• you fall asleep when you do not intend to, such as while having dinner,
talking, driving, or working;
• you collapse suddenly or your neck muscles feel too weak to hold up your
head when you laugh or become angry, surprised, or shocked;
• you find yourself briefly unable to talk or move while falling asleep
or waking up.
Although it is estimated that narcolepsy afflicts
as many as 200,000 Americans, fewer than 50,000 are diagnosed. It is as widespread
as Parkinson's disease or multiple sclerosis and more prevalent than cystic
fibrosis, but it is less well known. Narcolepsy is often mistaken for depression,
epilepsy, or the side effects of medications.
Narcolepsy can occur in both men and women at any
age, although its symptoms are usually first noticed in teenagers or young adults.
There is strong evidence that narcolepsy may run in families; 8 to 12 percent
of people with narcolepsy have a close relative with the disease.
Normally, when an individual is awake, brain waves
show a regular rhythm. When a person first falls asleep, the brain waves become
slower and less regular. This sleep state is called non-rapid eye movement (NREM)
sleep. After about an hour and a half of NREM sleep, the brain waves begin to
show a more active pattern again, even though the person is in deep sleep. This
sleep state, called rapid eye movement (REM) sleep, is when dreaming occurs.
Diagnosis is relatively easy when all the symptoms
of narcolepsy are present. But if the sleep attacks are isolated and cataplexy
is mild or absent, diagnosis is more difficult.
Although there is no cure for narcolepsy, treatment
options are available to help reduce the various symptoms. Treatment is individualized
depending on the severity of the symptoms, and it may take weeks or months for
an optimal regimen to be worked out. Complete control of sleepiness and cataplexy
is rarely possible. Treatment is primarily by medications, but lifestyle changes
are also important. The main treatment of excessive daytime sleepiness in narcolepsy
is with a group of drugs called central nervous system stimulants. For cataplexy
and other REM-sleep symptoms, antidepressant medications and other drugs that
suppress REM sleep are prescribed. Caffeine and over-the-counter drugs have
not been shown to be effective and are not recommended.
Learning as much about narcolepsy as possible and
finding a support system can help patients and families deal with the practical
and emotional effects of the disease, possible occupational limitations, and
situations that might cause injury. A variety of educational and other materials
are available from sleep medicine or narcolepsy organizations. Support groups
exist to help persons with narcolepsy and their families.
• Narcolepsy is a life-long condition that requires continuous medication.
• Although there is not a cure for narcolepsy at present, several medications
can help reduce its symptoms.
• People with narcolepsy can lead productive lives if they are provided
with proper medical care.
• If possible, individuals with narcolepsy should avoid jobs that require
driving long distances or handling hazardous equipment or that require alertness
for lengthy periods.
• Parents, teachers, spouses, and employers should be aware of the symptoms
of narcolepsy. This will help them avoid the mistake of confusing the person's
behavior with laziness, hostility, rejection, or lack of interest and motivation.
It will also help them provide essential support and cooperation.
• Employers can promote better working opportunities for individuals with
narcolepsy by permitting special work schedules and nap breaks.
National Center on Sleep Disorders Research (NCSDR)
Two Rockledge Centre
Suite 7024
6701 Rockledge Drive, MSC 7920
Bethesda, MD 20892-7920
(301) 435-0199
(301) 480-3451 (fax)
NHLBI Information Center
P.O. Box 30105
Bethesda, MD 20824-0105
(301) 592-8573
(301) 592-8563 (fax)
