Narcolepsy 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). Narcolepsy is the second-leading cause of excessive daytime sleepiness.1

Approximately 125,000 Americans are estimated to have narcolepsy. It strikes males and females and all races. Symptoms most commonly appear in a person’s teens and early twenties. The disease can vary in severity. 2

The condition is often associated with:

  • Cataplexy—a sudden loss of muscle tone and paralysis of voluntary muscles associated with a strong emotion
  • Sleep paralysis—immobility of the body that occurs in the transition from sleep to wakefulness
  • Hypnagogic hallucinations—pre-sleep dreams
  • Automatic behaviors—such as, for example, doing something “automatically” and not remembering afterwards how you did it.