Narcolepsy

Excessive Daytime Sleepiness

Nearly one in five Americans suffers from sleep disorders that result in excessive daytime sleepiness. Excessive daytime sleepiness can be a symptom of several sleeping disorders such as:

• Sleep apnea, a serious problem involving lapses in breathing during sleep and sometimes linked to heart problems
• Narcolepsy, a neurological disorder causing involuntary sleep episodes and temporary losses of voluntary muscle control (cataplexy) in some patients
• Restless legs syndrome (RLS)
• Periodic limb movement disorder (PLMD)
• Circadian rhythm disturbances, such as delayed sleep phase syndrome or adolescent insomnia
• Insomnia

An overnight stay at a sleep center is required to diagnose most sleep disorders.

Excessive daytime sleepiness can also be a symptom of various other neurological disorders, a side effect of certain medications, a result of head injury or a tumor, or a number of other medical conditions. If no other underlying disorder is found in someone with excessive daytime sleepiness, the condition is referred to as idiopathic hypersomnia (or primary hypersomnia).