is typically already very diminished or undetectable.
Functional Consequenc es of Narcolepsy 
Driving and working are impaired, and indivi duals with narcolepsy should avoid jobs
that place themselves (e.g., working with mach inery) or others (e.g., bus driver, pilot) in
danger. Once the narcolepsy is controlled wi th therapy, patients can usually drive, al-
though rarely long distances alone. Untreated individuals are also at risk for social isola-
tion and accidental injury to themselves or  others. Social relations may suffer as these
individuals strive to avert cataplexy by exerting control over emotions. 
Differential Diagnosis 
Other hypersomnias. Hypersomnolence and narcolepsy are similar with respect to the
degree of daytime sleepiness, age at onset, an d stable course over time but can be distin-