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Narcolepsy

• Overview
• Symptoms
• Treatment
• Prevention

Definition:

Narcolepsy is a sleep disorder that causes uncontrollable sleepiness and frequent daytime sleeping.

Alternative Names:

Daytime sleep disorder

Causes, incidence, and risk factors:

The exact cause of narcolepsy is unknown. Studies using gene markers show that the disorder may be genetic. A small group of neurons in the brain has been implicated in producing transitions from sleep to wakefulness and vice-versa. People with narcolepsy may have fewer of these neurons, or these neurons may have been damaged.

The disorder may be aggravated by conditions that cause insomnia , such as disruption of work schedules.

Narcolepsy is characterized by episodes of frequent, uncontrollable daytime sleeping, usually preceded by drowsiness . Sometimes, the person may start dreaming immediately upon falling asleep. The episodes usually occur after meals, but falling asleep may occur while working or driving a vehicle, having a conversation, being in any non-stimulating situation, or being in situations where there is little movement (sedentary situations).

There is a brief period of sleep, and the person awakens feeling refreshed. However, the person may again become uncontrollably sleepy a short time later.

Narcolepsy may also be associated with cataplexy, a brief episode of severe loss of muscle tone in various muscles. Generalized weakness may occur for a few moments during the transition between sleep and wakefulness (sleep paralysis). Many people with narcolepsy also have dreamlike hallucinations in the transition between sleep and wakefulness.

• Review Date: 9/7/2006
• Reviewed By: Kenneth Gross, M.D., Neurology, North Miami, FL. Review provided by VeriMed Healthcare Network.

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