Cataplexy is a medical condition which often affects people who have narcolepsy, a disorder whose principal signs
are EDS (Excessive Daytime Sleepiness), sleep attacks, and disturbed nightime sleep.
The term cataplexy originates from the Greekkata meaning down and plexis meaning a stroke or seizure, implying a falling-down seizure.
Cataplexy manifests itself as muscular weakness which may range from a barely perceptible slackening of the facial muscles to the dropping of the jaw or head, weakness at the knees, or the total collapse. Usually the speech is slurred, vision is impaired (double vision, inability to focus), but hearing and awareness remain normal. These attacks are triggered by strong emotions such as exhilaration, anger, fear, surprise, and laughter.
Cataplexy has so far only been found in subjects with narcolepsy and is therefore thought of as the same thing. Cataplexy is also sometimes confused with epilepsy, where a series of flashes may cause coma or stroke. Despite its relation to narcolepsy, cataplexy must be treated differently and separate medication must be taken.