Hypersomnia 885
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Hypersomnia refers to a set of related disorders that involve excessive daytime sleepiness.


There are two main categories of hypersomnia: primary hypersomnia (sometimes called idiopathic hypersomnia) and recurrent hypersomnia (sometimes called recurrent primary hypersomnia). Both are characterized by the same signs and symptoms and differ only in the frequency and regularity with which the symptoms occur.

Primary hypersomnia is characterized by excessive daytime sleepiness over a long period of time. The symptoms are present all, or nearly all, of the time. Recurring hypersomnia involves periods of excessive daytime sleepiness that can last from one to many days, and recur over the course of a year or more. The primary difference between this and primary hypersomnia is that persons experiencing recurring hypersomnia will have prolonged periods where they do not exhibit any signs of hypersomnia, whereas persons experiencing primary hypersomnia are affected by it nearly all the time. One of the best documented forms of recurrent hypersomnia is Kleine-Levin syndrome, although there are other forms as well.

There are many different causes for daytime sleepiness that are not considered hypersomnia, and there are many diseases and disorders in which excessive daytime sleepiness is a primary or secondary symptom. Feelings of daytime sleepiness are often associated with the use of common substances such as caffeine, alcohol, and many medications. Other common factors that can lead to excessive daytime sleepiness that is not considered hypersomnia include shift work and insomnia . Shift work can disrupt the body's natural sleep rhythms. Insomnia can cause excessive daytime sleepiness because of lack of nighttime sleep, and is a separate disorder.

Causes and symptoms

People experiencing hypersomnia do not get abnormal amounts of nighttime sleep. However, they often have problems waking up in the morning and staying awake during the day. People with hypersomnia nap frequently, and upon waking from the nap, do not feel refreshed. Hypersomnia is sometimes misdiagnosed as narcolepsy . In many ways the two are similar. One significant difference is that people with narcolepsy experience a sudden onset of sleepiness, while people with hypersomnia experience increasing sleepiness over time. Also, people with narcolepsy find daytime sleep refreshing, while people with hypersomnia do not.

People with Kleine-Levin syndrome have symptoms that differ from the symptoms of other forms of hypersomnia. These people may sleep for 18 or more hours a day. In addition, they are often irritable, uninhibited, and make indiscriminate sexual advances. People with Kleine-Levin syndrome often eat uncontrollably and rapidly gain weight, unlike people with other forms of hypersomnia. This form of recurrent hypersomnia is very rare.

The causes of hypersomnia remain unclear. There is some speculation that in many cases it can be attributed to problems involving the hypothalamus, but there is little evidence to support that claim.


Hypersomnia is an uncommon disorder. In general, 5% or fewer of adults complain of excessive sleepiness during the daytime. That does not mean all those who complain of excessive sleepiness have hypersomnia. There are many other possible causes of daytime sleepiness. Of all the people who visit sleep clinics because they feel they are too sleepy during the day, only about 5–10% are diagnosed with primary hypersomnia. Kleine-Levin syndrome is present in about three times more males than females, but it is a very rare syndrome.

Hypersomnia generally appears when the patient is between 15 and 30 years old. It does not begin suddenly, but becomes apparent slowly, sometimes over years.


Hypersomnia is characterized by excessive daytime sleepiness, and daytime naps that do not result in a more refreshed or alert feeling. Hypersomnia does not include lack of nighttime sleep. People experiencing problems with nighttime sleep may have insomnia, a separate sleep disorder. In people with insomnia, excessive daytime sleepiness may be a side effect.

The Diagnostic and Statistical Manual of Mental Disorders , which presents the guidelines used by the American Psychiatric Association for diagnosis of disorders, states that symptoms must be present for at least a month, and must interfere with a person's normal activities. Also, the symptoms cannot be attributed to failure to get enough sleep at night or to another sleep disorder. The symptoms cannot be caused by another significant psychological disorder, nor can they be a side effect of a medicinal or illicit drug or a side effect of a general medical condition. For a diagnosis of recurrent hypersomnia, the symptoms must occur for at least three days at a time, and the symptoms have to be present for at least two years.


There have been some attempts at using drugs to treat hypersomnia. No substantial body of evidence supports the effectiveness of these treatments. Stimulants are not generally recommended to treat hypersomnia as they treat the symptoms but not the base problem. Some researchers believe that treatment of the hypothalamus may be a possible treatment for hypersomnia.


Kleine-Levin syndrome has been reported to resolve occasionally by itself around middle age. Except for that syndrome, hypersomnia is considered both a lifelong disorder and one that can be significantly disabling. There is no body of evidence that concludes there is a way to treat the majority of hypersomnia cases successfully.



Aldrich, Michael S. Sleep Medicines. New York: Oxford University Press, 1999.

American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders. 4th edition, text revised. Washington DC: American Psychiatric Association, 2000.

Chokroverty, Susan, ed. Sleep Disorders Medicine: Basic Science, Technical Considerations, and Clinical Aspects. 2nd ed. Boston: Butterworth-Heinemann, 1999.

Sadock, Benjamin J. and Virginia A. Sadock, eds. Comprehensive Textbook of Psychiatry. 7th edition, vol. 2. Philadelphia: Lippincott Williams and Wilkins, 2000.

Thorpy, Michael J, ed. Handbook of Sleep Disorders. New York: Marcel Dekker Inc, 1990.


Boris, Neil W., Owen R. Hagina, Gregory P. Steiner. "Case Study: hypersomnolence and precocious puberty in a child with pica and chronic lead intoxication." Journal of the American Academy of Child and Adolescent Psychiatry 35, no. 8 (August 1996): 1050-1055.

National Center on Sleep Disorders Research Working Group, Bethesda, Maryland. "Recognizing Problem Sleepiness in Your People." American Family Physician (February 15, 1999): 937-38.


American Academy of Sleep Medicine. 6301 Bandel Road NW, Suite 101, Rochester, MN 55901. (507) 287-6006. <www.asda.org> .

Tish Davidson, A.M.

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Mar 4, 2008 @ 11:11 am
I am a nursing student trying to understand one of the cases in my hospital.He is a 12 year old boy,who has these episodes..where there is either drowsiness or excessive sleep day and night,with difficulty to speak,absolute loss of appetite even for days,failure to do daily activities like brushing,bathing and also mutism and posturing seen once. He also has hallucinations(visual)of people(or policemen)taking him away and he mutters to self and his father "forgive me,i did not do anything" there is no specific past history of any emotional stressor.He is diagnosed as HYPERSOMNIA but i wondered if patient could be so bad with this illness. pls help..and what treatment would u prescribe? THANK YOU,will wait for a reply
Julie Mommaerts
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Aug 12, 2009 @ 4:04 am
To whom this may concern,
My name is Julie Mommaerts, I am 16 and I can never sleep during the night, I was wondering if there is something wrong with me. I try to go to sleep at 8pm and never can. I sleep from 5-6am to 5-6pm. I am not obese, I eat right and I don't drink alcohol, or take any medications.. What is wrong with me.
Lakon Clayton
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Sep 20, 2009 @ 8:08 am
My name is Lakon Clayton. I am a 18 year old female & I am almost positive I have hypersomnia. How do they diagnose this?
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Oct 25, 2010 @ 10:10 am
How long a patients takes to get fully recovered from Hypersomnia... Is this disease fully recoverable and cureable or partly recoverable or is it is life long disease. What is the future of the patient suffering from Hypersomnia. Patient is 16 yrs old at present time and is suffering from last four years...
Jonathan Anderson
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Jun 23, 2011 @ 11:23 pm
i was diagnosed with Hypersomnia back in 2008 during my ET training while I was serving in the United States Navy at first i thought no i just like to sleep a lot because i'm young but after sleeping standing up numerous time they finally started me on meds while they decided what to do with me. After 3 months they finally decided to kick me out of the military which took a month with no benefits at all except unemployment that lasted a year and a half. Now all i do is sleep and take care of the house and my son 3 days a week while my wife barely supports us, i cant get a job because all is wanna sleep and i dont have insurance to cover the meds or doctor visits and i cant afford it out of pocket my memory is so bad i have to keep note pads around the house so i can remember what i need to do each day. and i normally sleep between 12 and 15 hrs a day and be told what day of the week it is some times. Other than the sleepiness and memory loss i'm fine as far as i know lol i just hope it doesn't get worse.

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