In this article:   Is There Any Treatment?   What Is the Prognosis?   What Research Is Being Done?   Resources

Narcolepsy is a disabling neurological disorder of sleep regulation that affects the control of sleep and wakefulness. It may be described as an intrusion of the dreaming state of sleep (called REM or rapid eye movement sleep) into the waking state.

Symptoms generally begin between the ages of 15 and 30. The four classic symptoms of the disorder are:

• excessive daytime sleepiness
• cataplexy (sudden, brief episodes of muscle weakness or paralysis brought on by strong emotions such as laughter, anger, surprise or anticipation)
• sleep paralysis (paralysis upon falling asleep or waking up)
• hypnagogic hallucinations (vivid dream-like images that occur at sleep onset)

Disturbed nighttime sleep, including tossing and turning in bed, leg jerks, nightmares, and frequent awakenings, may also occur. The development, number and severity of symptoms vary widely among individuals with the disorder. It is probable that there is an important genetic component to the disorder as well.

Unrelenting excessive sleepiness is usually the first and most prominent symptom of narcolepsy. Patients with the disorder experience irresistible sleep attacks, throughout the day, which can last for 30 seconds to more than 30 minutes, regardless of the amount or quality of prior nighttime sleep. These attacks result in episodes of sleep at work and social events, while eating, talking and driving, and in other similarly inappropriate occasions.

Although narcolepsy is not a rare disorder, it is often misdiagnosed or diagnosed only years after symptoms first appear. Early diagnosis and treatment, however, are important to the physical and mental well-being of the affected individual.

There is presently no cure for narcolepsy; however, the symptoms can be controlled with behavioral and medical therapy. The excessive daytime sleepiness may be treated with stimulant drugs or with the drug modafinil (Provigil), which was approved by the FDA for this use in 1999. Cataplexy and other REM-sleep symptoms may be treated with antidepressant medications. At best, medications will reduce the symptoms, but will not alleviate them entirely. Also, many currently available medications have side effects. Basic lifestyle adjustments such as regulating sleep schedules, scheduled daytime naps and avoiding "over-stimulating" situations may also help to reduce the intrusion of symptoms into daytime activities.

Although narcolepsy is a life-long condition, most individuals with the disorder enjoy a near-normal lifestyle with adequate medication and support from teachers, employers, and families. If not properly diagnosed and treated, narcolepsy may have a devastating impact on the life of the affected individual, causing social, educational, psychological, and financial difficulties.

The National Institute of Neurological Disorders and Stroke supports a broad range of clinical and basic research on sleep disorders including narcolepsy. NINDS has notified investigators that it is seeking grant applications in both clinical and basic sleep and wakefulness research, including basic and clinical research in narcolepsy. In 1999, a research team working with canine models identified a gene that causes narcolepsy -- a breakthrough that brings a cure for this disabling condition within reach. The researchers are currently searching for defective versions of this gene in people with narcolepsy.