• Reviewed on 12/12
    By Dr. Harrington

Narcolepsy: Overview

Narcolepsy is a condition that causes overwhelming drowsiness and sudden attacks of sleep. It affects 1 of every 2,000 people. Symptoms often begin in young adults and may be hereditary.



Symptoms of narcolepsy may include disturbed sleep, waking up often, and abnormal behavior. Other symptoms include:

Excessive sleepiness
This is often the first symptom of narcolepsy. It is often a lifelong condition. Sleep occurs during moments of inactivity or boredom. Sudden and unexpected sleep "attacks" can also occur at any time. Brief napping is common. Each nap lasts 10 to 20 minutes. Sleepiness is reduced after awakening from a short nap. The sleepiness increases again within the next two to three hours.

Cataplexy is the loss of muscle strength after an intense emotion. Emotions such as anger, fright, surprise, excitement, or laughter can cause this. It may occur without any cause and does not trigger loss of consciousness. Episodes may last from seconds to minutes. The loss of muscle strength may be mild, such as drooping of the eyelids, sagging of the jaw, or buckling at the knees. It may also be severe with complete lack of muscle strength causing the person to collapse.

Sleep paralysis
This is a brief loss of the ability to move. It occurs either at the start of sleep or upon awakening. Except for the eye muscles and those involved with breathing, all muscles are affected. Paralysis often lasts from a few seconds to a few minutes. Hallucinations and a sense of dread may also occur.

Sleep hallucinations
Sleep hallucinations may occur at sleep onset or upon wakening. A person may see shapes, colors, or actual figures; or, one may hear a sound or music, or feel movement. These feelings are often fearful, such as being attacked or escaping from danger.



Medicines may be prescribed for people with narcolepsy, and may be needed for life. Some people find brief naps helpful. 

More Narcolepsy Information
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