Narcolepsy is one of the causes of excessive daytime sleepiness (EDS).It is characterised by overwhelming daytime drowsiness and sleep attacks, causing the patient to fall asleep at the most inopportune moments, for example, while eating or during a meeting. It affects both genders equally and onset is usually in the puberty years. The exact causes of narcolepsy are unknown, but many patients with narcolepsy have increased destruction of the neurons that produce a wakefulness-promoting hormone called hypocretin. Research has also shown an association with genetics and exposure to certain influenza viruses.
