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Hypersomnia refers to either excessive daytime sleepiness or excessive time spent sleeping. When a person has this condition he has trouble staying awake during the day. A person with hypersomnia can fall asleep at any time. According to data from the National Sleep Foundation, up to 40% of people experience symptoms of hypersomnia from time to time.

What causes hypersomnia?

Several factors can cause hypersomnia. The most common ones are:

  • Another sleep disorder like sleep apnea
  • Obesity
  • Sleep deprivation
  • Drug or alcohol abuse
  • Prescription drugs including antihistamines or tranquilizers
  • Depression
  • Neurological diseases such as Parkinson’s disease or multiple sclerosis
  • Genetics

What are the types of hypersomnia?


Narcolepsy is a chronic neurological disorder. The most visible symptom of this disorder is excessive daytime sleepiness.  When a person has narcolepsy, he also experiences cataplexy and abnormal REM sleep. Narcolepsy is often characterized by extreme fatigue. A person with narcolepsy may fall asleep at inappropriate times.

Kleine-Levin Syndrome

Kleine-Levin syndrome is a rare disorder. A person with Klein-Levin syndrome has recurrent episodes of excessive sleep. This is often accompanied by cognitive and behavioral changes. It is not unusual for a person with this disorder to sleep for up to 20 hours per day. An episode of Kleine-Levin syndrome can last for a few days. Some episodes can last up to a few weeks.

Idiopathic Hypersomnia

Idiopathic Hypersomnia is a sleep disorder where a person feels excessively sleepy during the day. It is also very difficult to awaken from sleep a person with Idiopathic Hypersomnia. Even if a person suffering from Idiopathic Hypersomnia sleeps longer during the night, it won’t improve daytime sleepiness.

Insufficient Sleep Syndrome

Insufficient Sleep Syndrome is the most common cause of daytime sleepiness. This condition occurs when a person regularly fails to get sufficient sleep during the night. A person with this condition is unable to feel alert and well-rested during the day.

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Narcolepsy is a neurological disorder. It causes a disruption in the sleep and wakefulness state of the affected person. As a result someone with narcolepsy experiences excessive sleepiness and sleep paralysis. This sleep disorder is also characterized by hallucinations. In rare cases, a patient suffering from narcolepsy might experience episodes… Read More »Narcolepsy