Alternative Names

Daytime sleep disorder; Cataplexy

Definition of Narcolepsy

Narcolepsy is a sleep disorder that causes excessive sleepiness and frequent daytime sleep attacks.

Causes, incidence, and risk factors

Narcolepsy is a nervous system disorder, not a mental illness. Anxiety does not cause narcolepsy.


The most common symptoms of narcolepsy are:

Signs and tests

The doctor will perform a physical exam and order blood work to rule out conditions that can cause similar symptoms. Conditions that can cause excessive sleepiness include:


There is no known cure for narcolepsy. The goal of treatment is to control symptoms.

Expectations (prognosis)

Narcolepsy is a chronic, lifelong condition. It is not a deadly illness, but it may be dangerous if episodes occur during driving, operating machinery, or similar activities. Narcolepsy can usually be controlled with treatment. Treating other underlying sleep disorders can improve symptoms of narcolepsy.


Luc Jasmin, MD, PhD, Departments of Anatomy Neurological Surgery, University of California, San Francisco, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 9/2/2009

Sleep patterns in the young and aged

ADAM Medical Encyclopedia

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