[Narcoleptic syndrome].

Only in the last century was the narcoleptic syndrome recognized as a distinct entity fundamentally different from epilepsy. It is characterized by increased daytime sleepiness, usually as short sleep attacks, and by cataplexy. The latter is reflected in attacks of fully or incompletely developed loss of muscle tone, and in distressing akinetic states (so-called sleep paralysis) which chiefly occur in transition states between wake and sleep. In about half the patients, excessive daytime sleepiness may manifest itself in twilight states of lowered vigilance with automatic behaviour and amnesia. Many narcoleptics suffer from hallucinations, which may occur as they are falling asleep, during sleep paralysis, cataplectic attacks, and daytime sleepiness. Knowledge of the pathogenesis of narcoleptic disturbances is still incomplete but has been essentially widened by the discovery of paradoxical sleep, because cataplexy, sleep paralysis and hypnagogic hallucinations may now be interpreted as dissociated paradoxical sleep phenomena. The treatment of narcolepsy comprises advice in appropriate daily regimen, nutrition and vocational orientation as well as medication by stimulating agents for hypersomnolence and by tricyclic drugs for cataplexy.