Causes of Hypersomnia – Narcolepsy


  • M V Padma Srivastav


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.
Key words : EDS, Sleep, Narcolepsy