Hypersomnia – Understanding Over Sleeping and Excessive Drowsiness

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Written by:


, Sleep Researcher
Last Updated: Sun, November 25, 2018
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Marko Jevtic

, Sleep Specialist

Have you ever wondered if Sleeping Beauty actually fell asleep just like any other day and just “forgot” to wake up? Modern research on hypersomnia or excessive sleep shows that it is indeed possible for people, especially teenagers, due to modern lifestyle choices, almost 40% job holders in the US suffer from some form of a sleep disorder or the otherall asleep like Sleeping Beauty for long hours.

Hypersomnia or hypersomnolence occurs under the category of sleep-wake disorders in Diagnostic and Statistical Manual of Mental Disorders (DSM – 5). Now, you may be wondering if the bouts of extended hours of sleep and daytime sleepiness you have been experiencing off late are signs of hypersomnia. Thankfully, not all episodes of excessive sleep fall under the category of this neurological disorder. Unless you have been suffering from repetitive bouts of extended periods of rest and excessive daytime sleepiness for the past three months, you do not have to worry at all. Sleep-wake disorders like this one usually have a lasting impact on a person’s thinking and cognition.

Due to modern lifestyle choices, almost 40% job holders in the US suffer from some form of a sleep disorder or the other. Interestingly, doctors, nurses, and researchers are no exception.

What is the Correct Definition of Hypersomnia?

The medical community refers to hypersomnia through various names including the more common hypersomnolence. One of the prominent signs of it includes excessive sleepiness during the daytime. This form of sleep disorder involves sleep drunkenness, disorientation, confusion, slowness, and poor coordination. However, hypersomnia does not include the classic sleep attacks usually seen in case of narcolepsy Type I and Type II.

There is a significant lack of immunogenetic features and polysomnograph evidence to characterize hypersomnolence. Sometimes, people with this particular disorder fall asleep during any time of the day, and they might also suffer from other sleep-related problems that begin with a chronic lack of energy during the daytime.

Case Studies of Hypersomnia

A recent publication by the Sleep Research Society studied the sleep disorder database of over 6000 patients from all states of the US. All of them had some form of sleep disorder that doctors had previously diagnosed.

The study involved a retrospective study of the 777 patients with idiopathic hypersomnolence. It showed that these people were more likely to experienced long duration of unsatisfactory daytime naps and slow-wave sleep. Most of the idiopathic hypersomnolence patients had a family history of sleep-wake disorders.

About 89% of the patients had a history that spanned several years, and only about 11% of them showed spontaneous remission. This kind of natural cure is absent from cases of narcolepsy. Several forms of hypersomnia and excessive daytime sleepiness show improvement over time with continuous medication and unique combination of sleep-modifying drugs.

What Causes Excessive Drowsiness During the Daytime and Hypersomnia?

There can be several causes of excessive daytime sleepiness and hypersomnia. The reasons can vary considerably depending on the age, profession, and lifestyle of the sufferer. It can result in an arbitrary classification of the disease, symptoms and their causes. Here are some of the more prominent causes of the disorder;

  1. Several sleep disorders including narcolepsy and sleep apnea can give rise to this condition of excessive sleep.
  2. Weight management problems and lack of exercise are other prominent causes.
  3. Sleep deprivation can build the foundation for EDS in the long-run.
  4. A long history of drug abuse and alcohol abuse can also contribute to hypersomnia.
  5. Excessive use of tranquilizers, new antidepressants, and mood stabilizers often lead to EDS symptoms.
  6. Excessive sleepiness can have a strong genetic influence as well.
  7. Sometimes, EDS can be a symptom of neurodegenerative diseases like Alzheimer’s and Parkinson’s.
  8. New or old head injuries can lead to abnormally long hours of sleep.
  9. Autoimmune diseases including Multiple Sclerosis can lead to hypersomnia in many.
  10. Endocrine diseases and metabolic disorders.
  11. Infections and toxin-induced hypersomnia like in the case of sleeping sickness.
  12. Long recurrence of depression and depressive episodes can exacerbate EDS and hypersomnia.

In the general population, the complaints of excessive daytime sleepiness are often as frequent as 5 out of 100 adults. Between 5% and 10% of the people, who check into sleep clinics with complaints of excessive drowsiness during the daytime receive idiopathic hypersomnia (IH) diagnosis. It is only 0.5 times as common as narcolepsy.

In a study involving 77 patients, the mean age of diagnosis was around 30. The onset usually occurs between 10 and 30 years of age. The mean age of onset of IH among the observed group of patients was about 17. It has no gender bias, and in a larger group of subjects, hypersomnia usually affects 4% to 6%. As you can see, the epidemiology of hypersomnia is distinct from that of Idiopathic Hypersomnia. The latter is a subset of the sleep-wake disease, although several people use the terms synonymously.  

Why is the Differential Diagnosis of Hypersomnia Necessary?

Since this sleeping disorder can be of various types, medical professionals, sleep experts, and researchers often require learning the specific nature of the disease to treat it properly. Some individuals have more than one form of hypersomnia, and they need particular treatment that can address the causes at the very roots. Even when the reason for a specific case of excessive daytime sleepiness is apparent, the expert needs to assess the exact extent of the contribution of this cause to the EDS for dispensing proper treatment.

Hypersomnia can be primary or secondary hypersomnia mimics. Having more than one underlying causes often means juggling more than one type of the sleeping disorder throughout life. The complications due to multiple underlying conditions result in difficulties during diagnosis. For example, people suffering from obstructive sleep apnea may experience EDS due to obstructions in their airway, but there can be additional factors like obesity, brain hemorrhaging or narcolepsy that may contribute to the severity of their disease.

What are the Primary Hypersomnias?

There are only a few forms of true primary hypersomnias including narcolepsy, Klein Levin syndrome and idiopathic hypersomnia.

Primary Hypersomnia Mimics

Several genetic diseases can contribute to sleep disorders like hypersomnia. Norrie disease, Niemann-Pick syndrome, myotonic dystrophy and Prader-Willi syndrome are some of the most prominent causes of hypersomnia. The precedence of EDS in these cases usually occurs with other diseases that include several secondary objectives. For example, cases of myotonic dystrophy occur alongside sleep onset REM periods (SOREMPs) like narcolepsy.  

In each of these cases, it is essential to rule out the secondary causes of the disease. There have been reported cases of secondary narcolepsy in individuals with a head injury that was initially asymptomatic.

What are the Frequent Cases of Secondary Hypersomnias?

Sleep quality altering diseases reduce the duration and frequency of restorative sleep. It leads to feelings of excess fatigue during the daytime, during which people find themselves dozing off without any preface.

Over the years, scientists have also associated several mood disorders, chronic depression, bipolar disorder and anxiety disorders with EDS. Multiple medications, especially antidepressants and mood-altering compounds can interfere with sleep duration. It is essential to wean off these medicines to prevent any form of withdrawal. Chronic sleep deprivation as a result of lifestyle choice also contributes to symptoms of secondary hyper-sleep considerably.

What is the Treatment for Hypersomnia?

At present, there is no complete cure for the disorder. It is mainly due to the massive number of variations in the causes and the symptoms of it. However, research shows that management of lifestyle and improvement of sleep hygiene can make a huge difference in the quality of rest the patients get each night. It is quite the same for people with idiopathic hypersomnia (IH).

There are no specific cures since scientists and researchers do not understand the mechanism of this sleep-wake disorder completely. You will find several FDA approved the medication for narcolepsy, but there are hardly any of the different forms of primary hypersomnia and primary hypersomnia mimics.

There are several wake-promoting medications that doctors often prescribe for narcolepsy, but people often use them for treating their IH. The lack of documentation and studies on these treatments make the treatment quite risky for all. In fact, several patients do not achieve the same level of remission with the same medications that treat narcolepsy Type I and Type II.

Behavioral therapy does not work as well for IH as it does for other sleep-wake disorders. There is little evidence that proves the impact of sleep hygiene improvement on this disease. You might be tempted to try out polyphasic sleeping patterns and planned naps, but years of observation and investigation have shown that these naps are usually for long hours and unrefreshing. However, behavioral therapy can help in controlling the emotional responses to EDS.

Losing hours of work and social life to excessive sleep can invoke anger, frustration, and depression in many. Extensive counseling is often necessary for new partners of people suffering from prolonged episodes of IH. Children often require additional emotional support due to the lack of social life, and friends.

In several cases of idiopathic hypersomnia, experts have recommended the use of conservative behavioral therapy that focuses on behavioral modifications. Some of these behavior modification programs and counseling sessions often bear more significance with the simultaneous introduction of modafinil and atomoxetine like medications.

Some of the treatments need to be more aggressive with the introduction of wake-promoting agents like sodium oxybate and other high dose stimulants since CNS stimulants are lesser active than they usually are for narcolepsy. The approach towards the treatment and management of IH needs to be empirical and not generic.

Is there a Treatment for Recurrent Primary Hypersomnia?

While most of us would love to sleep on the weekdays and occasionally sleep until afternoon, we do not think that someone, somewhere in the world sleeps for 23 hours a day.

Imagine missing most of your life because you are sleeping all the time and when you are awake, you are dazed, and someone is force feeding you and keeping you clean. It is the “Sleeping Beauty” syndrome (Kleine-Levin Syndrome) we had referred to earlier. This syndrome can affect both boys and girls. The symptoms begin without any warning when they are in their early teens. As a result, they end up missing most of their school life, their friends, the Prom, and almost everything else. Even getting a driver’s license becomes impossible until the syndrome simply ups and leaves, as suddenly as it came.  

People suffering from Kleine-Levin Syndrome or the Sleeping Beauty syndrome often wake up to binge on high-calorie food, carry out compulsive behaviors and engage in childlike actions. Sometimes they have heightened sex drive and apathy to go with excessive sleep. The period between two bouts of Kleine-Levin Syndrome can last between 6 months to 12 months, during which the sufferer experiences regular rest. Although it is a rare disorder, keen observation and forum discussion at the Kleine-Levin organization shows that irritability, obsessive behavior, and lethargy often precede an episode.

It is indeed a form of primary hypersomnia that goes away on its own after the sufferer reaches adulthood. It is the only form of hypersomnia that goes away completely with time. The syndrome is common among men, although it lasts longer in women. There is no particular genetic link or infection related pathway that explains the occurrence of the Kleine-Levin Syndrome. The only known medication that works against the sleeping beauty syndrome right now is Lithium, the mood stabilizer doctors often prescribe for manic depression or bipolar disorder.  

What’s the Difference Between Narcolepsy and Idiopathic Hypersomnia?

Narcolepsy and idiopathic hypersomnia are both diseases belonging to the class of primary hypersomnia. They are the central disorders of hypersomnolence (CDH) that share considerable similarities. For example, patients with either narcolepsy or IH exhibit EDS.

One of the best diagnostic tests that can distinguish between each disorder is by utilizing multiple sleep latency (MSL) tests and polysomnography. These tests elicit the number of sleep onset REM periods (SOREMPs) a patient experience. Patients with narcolepsy usually go through at least 2 SOREMPs, but patients with IH don’t.

There are several other diagnostic symptoms for each of these syndromes. Here’s a brief list of the symptoms for each.

Narcolepsy. Patients suffering from narcolepsy usually do not sleep for extended hours. They find small naps more refreshing. Sleep paralysis, sleep inertia, and other sleep-wake transition disorders are more common among people suffering from narcolepsy. Visual and auditory hallucinations during sleep onset-offset periods are very common for them too. People with narcolepsy often experience episodes of cataplexy (loss of muscle control) in response to sudden emotions.

IH. People with IH often suffer from sleep inertia and confusional arousal. However, they also sleep for more extended hours. Periodic napping hardly helps since these naps can extend for long hours and turn out to be utterly unrefreshing. They usually have problems waking up to alarm clocks and other external stimuli, although it is not a circadian rhythm disorder. In essence, their excessive daytime sleepiness is independent of the duration of their nighttime rest.

Is Idiopathic Hypersomnia the Same as Hypersomnolence?

Several blogs and articles on the web use IH and hypersomnolence interchangeably, although they are different from each other. IH is a subclass of primary hypersomnia. In a way, you could say that all cases of IH are also cases of hypersomnia, but all instances of hypersomnia are not IH. Medically, IH is the same as primary hypersomnia, HI, central hypersomnia and hypersomnia of the brain origin. For example – DSM IV defines idiopathic hypersomnia as EDS without the instance of narcolepsy. It is a subset of primary hypersomnia since it occurs without the cases of secondary hypersomnia causes.

Since it is the hypersomnia of the brain origin, GABA receptors may have an important role to play in this disorder. Although popular medications for other forms of secondary and primary hypersomnias are ineffective for IH, GABA-directed medications sometimes work in alleviating the symptoms of this sleep-wake disorder. These medications currently include variants of clarithromycin and flumazenil.

IH is a lifelong disorder, unlike the Kleine-Levin Syndrome. The symptoms usually begin with the onset of puberty, but unlike the latter, the symptoms do not disappear with age. It is a progressive disorder, but effective medication and improvement in sleeping habits can stabilize it. It has profound social and professional consequences just like any other primary hypersomnia. Therefore, it is easy to confuse IH with hypersomnia.

What is the Prognosis of Hypersomnia?

Hypersomnia is a heterogeneous disorder. Therefore, its prognosis depends on the cause of the particular case at hand. It is understandable that the prognosis of Kleine-Levin Syndrome will vary considerably from that of narcolepsy. As we have mentioned before, the cause of hypersomnia can be a tumor, stroke, head injury, autoimmune disease or a neurodegenerative disease. The only way to treat a complex disorder as this one is by addressing the cause at a grassroots level.

Most often, hypersomnia is not a life-threatening condition. However, this disorder has severe consequences including a higher risk of automobile accidents, higher risk during operation of heavy machinery, prolonged absence from work or school without legit explanation. In most cases, people are unsympathetic towards young students or adult job holders, who seem physically healthy, but sleepy all the time.

Modern culture has little tolerance for daytime sleepiness and the “laziness” that arises from it. It is also due to the lack of enough awareness about the disease. It can compromise one’s cognition and decision-making abilities as well. It takes a hefty toll on people’s social associations, career, and personal life. Educating relatives, friends, and colleagues or teachers helps the sufferer manage the disorder better than before.

What are Some of the Recent Research on Hypersomnia that Gives us Hope?

Research on the subject of hypersomnolence has been ongoing for the last several decades. There have been a few breakthroughs in the diagnostics, and treatment of the same. Here are the few examples from the scientific papers and recent publications.


Recent research on several subjects suffering from Narcolepsy shows that their bodies have an abnormally low level of Acylcarnitine. In case of similar studies of hypersomnolence in mice, researchers have noticed a similarly lower level of acylcarnitine. In case of mice, the deficiency causes a significantly higher frequency of fragmented sleep and REM sleep. It also reduces locomotor activity in these subjects.

Another study on human subjects shows that when people suffering from hypersomnia received supplements of L-carnitine, they showed lesser hours of daytime sleepiness as compared to a control group, who received a placebo.


Melatonin has to be one of the most popular compounds that sleep experts and doctors use for the treatment of sleep disorders. Several studies have used slow release (SR) melatonin at a dose of 2 mg during bedtime. It has reportedly relieved daytime sleepiness and sleep drunkenness in the patient subjects about 50% of the times.


Off late, there have been several studies that suggest the use of levothyroxine for the treatment of IH. That is potential miracle molecule that can cure subclinical hypothyroidism in human beings. However, there is a massive caveat to this treatment that is keeping it from extensive human trials. Repetitive therapy with levothyroxine can cause cardiac arrhythmia in mammalian subjects.

Hypocretin Agonists

Hypocretin-1 is one of the most robust wake-promoting molecules in animal models of research. However, it does not cross the blood-brain barrier. Recent publications on the treatment of insomnia show the creation of a hypocretin receptor for the animal brain. It is indeed possible for the scientists to create something similar, but a hypocretin agonist for the treatment of hypersomnia.


In a world, where the treatments of central hypersomnia disorders are few, researchers have to make the most of what they have. Clarithromycin has recently become famous as the miracle drug that can treat and potentially control hypersomnia.

It is one unique compound that has GABA modulating qualities. However, it is still in phase 2 clinical trial levels, and not much is public about the effects of clarithromycin on the overall health of individuals suffering from hypersomnia.  

What is an Exceptional Case of Hypersomnia?

Very recently, the American Sleep Association has included the human form of African sleeping sickness or African trypanosomiasis. It is a disease that causes a hyperimmune reaction that keeps the sleep cycles undisturbed in the initial phases of the disease. It is entirely different from the immune response to HIV and Whipple’s disease cause.

During the infection of these two diseases, the auto-antibodies send the infected person to a sleepless hyperdrive in the initial stages of the disease. However, as the disease progresses and the trypanosomes enter the meninges, and the brain, auto-antibodies against the nervous system take over and send the patient into a stage of comatose sleep for long hours. The entry of the trypanosomes into the CNS disrupts the sleep-wakefulness cycles. It results in the disappearance of the circadian rhythmicity of the patient’s sleep-wake transitions. There is a general absence of conventional sleep structures, and the excessive sleep can occur at any time.

The treatment of this form of secondary hypersomnia usually depends on the kind of infection. For example, trypanosomiasis is a protozoan disease that requires intensive treatment involving several doses of strong antibiotics such as pentamidine, suramin, nifurtimox, and melarsoprol.

Similarly, if Whipple’s disease or HIV is the cause of hypersomnia in a patient, the treatment should be to treat and eliminate the causal organism, rather than to dispense symptomatic treatment.

Why is Learning About Hypersomnia so Important?

We have all heard about that one person, who falls asleep everywhere or the other person who slept at least 8 hours at night but was always tired. When we gossip about such individuals, we rarely take into account that this can happen to us tomorrow. Take for example the case of Danielle Hulshizer. She fell asleep before midnight, every night, but never felt fresh after waking up. She was one of those people, who are most likely to say “five more minutes” after the alarm went off. There were times when her fiancé would pick her up from bed physically to see if she would stand. Even that would be a failed attempt at times since she would slump right back on the mattress or on the floor and continue sleeping.

It seems fine as long as the person is living alone or has flexible job hours. For people with a family or a new partner, managing their sleep schedule along with meeting their family and social responsibilities become impossible. That is one of the reasons adults with flexible job hours often find it easier to manage their hypersomnolence without medical intervention. However, those are rare cases, since for most adults suffering from EDS it starts to interfere with their family life. Therefore, most doctors recommend family counseling along with other medication and behavior therapy as ways to manage instances of excessive daytime sleepiness.

More sleep is rarely helpful for these people. It causes more distress than de-stressing. It often leads to chronic pains of the lower back, stiffness of muscles on the shoulders and neck, terrible headaches and blood pressure problems. Imagine waking up tired after 12 long hours of sleep, or maybe you do not have to! If you recognize more than one symptom we have mentioned here, it is time for you to visit a sleep specialist.

As you can see, hypersomnia or excessive sleep is rarely a case of laziness. It is a severe disorder that affects every aspect of a person’s life. Visiting a doctor is always the best thing to do before you start taking stimulating medication. As we have mentioned before, hypersomnia can have more than one cause, the treatment of this disorder can be quite complicated. Although many forms of primary hypersomnia are not completely curable, they are easily manageable thanks to modern medical research and technology. You will need to undergo polysomnography and other SOREMPs tests to confirm the diagnosis, but at the end of it all, staying awake to appreciate an entire day is worth it!

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