Narcolepsy

A. Irresistible attacks of refreshing sleep that occur daily over at least 3 months. 

B. The presence of one or both of the following: 

(1) cataplexy (i.e., brief episodes of sudden bilateral loss of muscle tone, most often in association with intense emotion) 
(2) recurrent intrusions of elements of rapid eye movement (REM) sleep into the transition between sleep and wakefulness, as manifested by either hypnopompic or hypnagogic hallucinations orsleep paralysis at the beginning or end of sleep episodes

C. The disturbance is not due to the direct physiological effects of a substance(e.g., a drug of abuse, a medication) or another general medical condition.

Reprinted with permission from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision. Copyright 2000 American Psychiatric Association