Causes of Hypersomnia – Narcolepsy.

ABSTRACT

The causes of hypersomnia or excessive daytime sleepiness (EDS) besides volitional sleep deprivation and obstructive sleep apnea are principally due to primary central nervous system abnormalities. Most common amongst these is Narcolepsy, a primary disorder of the neural control of wakefulness and sleep. The recent discovery of hypocretin/orexin deficiency as the main cause of narcolepsy will lead to important therapeutic advances for patients with narcolepsy and further to understanding of the control of sleep and wakefulness in general. Importantly, the excessive daytime sleepiness is not due to psychiatric conditions, but rather is always due to sleep deprivation or an underlying diagnosable and treatable sleep disorder.