Also known as: Gelineau's syndrome, Paroxysmal sleep, Sleep epilepsy, Narcoleptic syndrome, Sleep paralysis
Narcolepsy is a rare disorder characterized by chronic, excessive attacks of drowsiness during the day, sudden extreme muscle weakness (cataplexy), hallucinations, paralysis while sleeping, and disrupted sleep during the night. Attacks of drowsiness may persist only a few minutes or last for hours, and may vary in frequency from a few incidents to several during a single day. Although the exact cause of narcolepsy is not known, many researchers suspect that genetic factors play a role in the development of the disorder.