Hypersomnia: Symptoms, Causes, Definition and Treatments

Written by

Afy Okoye , Staff Writer, Sleep Health

Reviewed by

Dr. Michael Breus, PhD, DABSM, FAASM , Clinical Psychologist, Sleep Medicine Expert
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Hypersomnia refers to excessive sleepiness and it is characterized by an individual having difficulty staying awake throughout the day.

People with hypersomnia can fall asleep at any time and in any condition, even while driving or at work.  The primary symptoms of hypersomnia are prolonged nighttime sleep and excessive daytime sleepiness, with the desire to take several long naps during the day.  This condition is more prevalent in men than in women, affecting approximately 5% of the population.

What Are The Symptoms Of Hypersomnia

Hypersomnnia, or excessive daytime sleepiness (EDS), is usually a symptom of a larger condition.

“Hypersomnia is being extremely sleepy during the day”

Those with hypersomnia suffer from constant, recurrent episodes of extreme sleepiness and symptoms of sleep deprivation.  It can be caused by other disorders such as narcolepsy, obstructive sleep apnea, and the use of some types of medications, including melatonin and sleeping aids. (1)

There are several tests that can be done to diagnose hypersomnia, which will determine whether the individual has primary (originating in the brain) or secondary (originating as a result of another disease) hypersomnia. (2)

First, the physician will look for other obvious sleep disorders that could be causing the excessive sleepiness, with the primary goal being to determine if there are treatable medical conditions present.  These tests could include polysomnography, subjective scales such as the Epworth Sleepiness Scale and the Stanford Sleepiness Scale, as well as objective tests like the multiple sleep latency test.  The physician will usually make the diagnosis when symptoms have been present for three consecutive months and there are no other underlying diseases. (3)

Differences Between Primary Hypersomnia & Secondary Hypersomnia

Primary hypersomnia is rarer than secondary hypersomnia, affecting less than 1% of the population and usually associated with a more widely known diagnosis.  Primary hypersomnia includes diagnoses such as narcolepsy, idiopathic hypersomnia, and Klein-Levin syndrome (recurrent hypersomnia).

 It is notable that primary hypersomnia is often associated with genetic disorders including, but not limited to, myotonic dystrophy, Prader-Willi syndrome, and Norrie disease; however, the hypersomnia may be considered a secondary symptom in many of these cases.

Neurological disorders may also resemble hypersomnia.  Problems like brain tumors, lesions, and dysfunctional thalamus, hypothalamus, or brainstem may lead to excessive sleepiness.  Further, diseases like Alzheimer’s and Parkinson’s may have symptoms that look like primary hypersomnia as well. (4)

 Secondary hypersomnia is much more prevalent.  The excessive sleepiness can be a result of other conditions such as depression, obesity, epilepsy, or multiple sclerosis.  It is common in those with upper airway resistance syndrome, restless leg syndrome, sleep deprivation, and substance abuse.  Some people may be genetically predisposed to the condition as well.

Common Conditions That Lead To Hypersomnia

There are a host of conditions that could lead to hypersomnia; however, the most common cause is Sleep Apnea, affecting approximately 4% of the population.

Natural & Prescribed Treatments for Hypersomnia

Treatment will depend greatly on the underlying cause of hypersomnia and whether it is a primary or secondary concern.  Sometimes, catching up on sleep will alleviate the excessive sleepiness; however, more often than not, it is more appropriate to treat the underlying cause than it is to treat the symptom.  Most common treatments include the use of stimulant medications like amphetamines to help the individual stay awake throughout the day. (5)  In addition, behavioral therapy, sleep hygiene, and education are usually added to a treatment regimen.

Idiopathic hypersomnia & narcolepsy are related to EDS. Hypersomnia is a sleep symptom defined as excessive daytime sleepiness.

Primary Hypersomnia is a sleep disorder that shares many similarities with narcolepsy in terms of symptoms. However, it lacks the classic ‘triad of narcolepsy symptoms.

People with primary hypersomnia will often sleep in excess of 10 hours, and are very difficult to wake during this time. Despite what would be considered an abundance of sleep for most people, they will still feel tired during the day, and may feel compelled to nap multiple times, even at times or in places that would not be considered socially acceptable. Like the prolonged sleep periods, these naps often provide only short periods of relief from the chronic tiredness, and another desired nap session will quickly approach.

Hypersomnia may be caused by other sleeping disorders, though these would generally be categorized as such , and not as hypersomnia. It may also be a case of genetics in some people, and could also be the cause of certain drugs or medications, brain damage, or other medical disorders like fibromyalgia. In some cases, hypersomnia has no directly attributable cause and these cases are classified as idiopathic hypersomnia.

Primary Hypersomnia is a relatively rare sleeping disorder, affecting under 1% of the population. It is slightly more common in females than in males, and typically starts in early adulthood. It is very rarely found in children.

Diagnosing hypersomnia will require some tests to make ensure there aren’t any other medical conditions or sleeping disorders causing the excessive sleepiness. A doctor may want you to maintain a sleep diary for one or more weeks before setting up these tests, and will also want to know the length of time the excessive daytime sleepiness has afflicted you for. A diagnosis of hypersomnia will probably not be made unless the offending symptoms have been around for at least three uninterrupted months, and with no apparent cause.

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Tools To Detect Hypersomnia

Polysomnogram and multiple sleep latency tests are both good tools in detecting hypersomnia or other sleeping disorders. The multiple sleep latency test measures the speed at which a person enters deep sleep over numerous 2 hour intervals. People with hypersomnia and other related disorders like narcolepsy tend to fall asleep very quickly, and this is considered the best test for detected these sleeping disorders. A multiple sleep latency test of less than 10 minutes may indicate one of the above sleeping disorders. The polysomnogram test measures the subject’s brain waves and bodily movements during sleep phases, and this is good for detecting other sleep disorders that may be leading to the daytime sleepiness. If nothing abnormal is detected during this sleep test, you may be asked to come back for a 2nd test to validate the data, and barring changes in the results, it may be determined that you have hypersomnia.

Primary Hypersomnia is most commonly treated with stimulants like amphetamine and modafinil. Other treatments could include antidepressants. Behavioral changes are also instituted in most cases, and for those with idiopathic hypersomnia, this is one of the only treatment methods available at present.

Proper sleep hygiene is the most important behavioral change that must be implemented. This includes setting a regular sleeping schedule, having a sleeping environment that is well suited to quality sleep, a comfortable bed and pillow, and avoiding caffeine or other stimulants near bedtime.

Natural Treatments for Hypersomnia

Some treatment plans may include an attempt at avoiding naps completely through the use of daytime stimulants, others will attempt to remove naps systematically, while others will encourage naps in balanced doses and at proper times and locations. How hypersomnia gets treated, and with what ultimate goal(s) in mind is up to the patient, and these should be ambitious yet realistic.

Hypersomnia Summary

Hypersomnia, or excessive daytime sleepiness, is a very common finding in our society that has many causes and many treatment options. If you think that you have these symptoms, talk to your doctor about hypersomnia.

About The Author

Afy Okoye

Staff Writer, Sleep Health

Afy is a writer and creative strategist in San Francisco with a master’s degree in international health policy from the London School of Economics. She has written for VeryWell Health, BlackDoctor.org, and Paste magazine and edited peer-reviewed journal manuscripts for Elsevier. Afy says her work with The Sleep Doctor is anything but “sleepy.” She enjoys the opportunity to learn new information and share knowledge that gives people the power to make better choices. Afy also likes to read non-fiction, do creative writing, and travel solo.

  • Position: Side Sleeper
  • Temperature: Hot Sleeper
  • Chronotype: Bear

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