Narcolepsy is a neurological disorder that results in excessive sleepiness. Abnormalities of the neurochemical "hypocretin" have been implicated in the pathophysiology of narcolepsy. Since narcolepsy is a disorder that involves rapid eye movement sleep (REM), it mirrors the phenomena that occur in REM. The characteristic symptoms of narcolepsy include the following:
Daytime sleepiness is the hallmark of narcolepsy. Narcolepsy sufferers complain of being tired and sleepy throughout the day, but are often temporarily refreshed by short naps.
Sleep attacks where individuals suddenly fall asleep can happen while engaged in normal activities such as driving, walking and at work
Disturbed night time sleep: Narcoleptics have restless sleep, wake up frequently, and have trouble going back to sleep.
Hypnagogic hallucinations reflect the fact that the dreams are so vivid that they appear real and individuals may feel that what is being dreamt is actually happenning. This is especially seen at sleep onset.
Memory problems may be experienced because individuals may not be fully awake during those events. Furthermore, the details of events and conversations may be affected by dream phenomenon.
Sleep paralysis is when an individual is unable to move for a few seconds or minutes either while falling asleep or waking up.
Cataplexy is a symptom that is uniquely seen in Narcolepsy and is characterized by sudden loss of muscle tone and weakness. Cataplexy may be localized to a few muscle groups, when a limb, the head, or the muscles of the face become weak. It can also be generalized to involve the whole body. Cataplexy is normally caused by strong emotions such as laughter, excitement, and surprise.
Narcolepsy may be primary or secondary. Primary narcolepsy is seen in about one out of every 2,000 people, and it affects men and women equally. Primary narcolepsy does seem to have a genetic basis to it and the risk for narcolepsy increases when a relative has it.
Narcolepsy may be seen with and without cataplexy.Narcolepsy usually starts during adolescence or early adulthood and may be a lifetime disorder.
Secondary narcolepsy may be seen after head trauma, neurological injury and infections.
In addition to the history, an overnight sleep study or NPSG followed by a daytime nap study or MSLT are necessary to confirm the diagnosis of narcolepsy. A sleep diary for the two weeks preceding the testing is imperative and a drug screen may need to be performed at the time of the studies.
Other blood tests may also need to be done.
The most common way to treat narcolepsy is by using medications. Stimulants are used for the excessive daytime sleepiness. Other kinds of medications may need to be used to control the cataplexy component of the disorder.