narcolepsy

n. disease characterized by uncontrollable sleep attacks (Pathology)

Narcolepsy is a neurological condition most characterized by Excessive Daytime Sleepiness (EDS). A narcoleptic will most likely experience disturbed nocturnal sleep, which is often confused with insomnia, and disorder of REM or rapid eye movement sleep. It is one of the dyssomnias. A narcoleptic may also sleep at any random time.
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Narcolepsy is a disorder marked by excessive daytime sleepiness, uncontrollable sleep attacks, and cataplexy. [more]Narcolepsy - Community and Resources

Noun
1. a sleep disorder characterized by sudden and uncontrollable episodes of deep sleep; "he believes that narcolepsy is attributable to an inability to suppress REM sleep during waking"
(hypernym) hypersomnia

Synonyms and related words:
catalepsy, coma, encephalitis lethargica, high, lethargy, narcohypnosis, narcoma, narcosis, narcotic stupor, narcotization, nod, sedation, shock, sleeping sickness, sopor, stupor, swoon, thanatosis, trance