To hear audio pronunciation of this topic, purchase a subscription or log in.

[Gr. narke, numbness, + lepsis, seizure]
A disorder marked by recurrent, uncontrollable attacks of daytime sleepiness, often associated with temporary muscular paralysis (cataplexy), which may occur after powerful emotional experiences. People affected by this condition may have several sleep attacks each day. Typically, narcoleptic patients arouse from sleep relatively easily.
narcoleptic (năr-kō-lĕp′tĭk)
To hear audio pronunciation of this topic, purchase a subscription or log in.
, adj.

Narcolepsy occurs in families, and about 90% of affected people have specific human leukocyte antigens (HLA-DQw6 or HLA-DR2). People with narcolepsy have diminished levels of peptides in the brain, called orexins, that influence sleep and consciousness.

Scheduled naps during the day may prevent sleep attacks, especially if the naps are timed to occur when the patient usually experiences sleep attacks. Drugs used to treat narcolepsy include stimulants such as dextroamphetamine sulfate, pemoline, or methylphenidate hydrochloride.

Descriptive text is not available for this imageNarcoleptics should avoid activities that require constant alertness, e.g., driving or flying. At the first sign of drowsiness, affected patients should seek a safe place to sleep. In many states in the U.S., loss of consciousness is grounds for revocation of driving privileges. Patients with narcolepsy should review their motor vehicle usage with their health care professionals.

There's more to see -- the rest of this topic is available only to subscribers.