People with idiopathic hypersomnia feel sleepy during the day even if they slept for the recommended minimum of 8 hours during the previous night, and they are experiencing chronic excessive daytime sleepiness. Idiopathic hypersomnia is a neurological sleep disorder which belongs to the group of hypersomnias.
While most of us are sleep deprived and always in need for a few more hours in a day, some people who sleep over the vast majority of their time, similar to babies who sleep up to 19 hours. For babies, that is an optimal amount of sleep, but for adults, sleeping so much is an indicator of a sleep disorder called idiopathic hypersomnia.
People with this disorder will feel sleepy during the day even if they slept for the recommended minimum of 8 hours during the previous night, and they are experiencing chronic excessive daytime sleepiness. Idiopathic hypersomnia is a neurological sleep disorder which belongs to the group of hypersomnias, we differ primary hypersomnia which occurs on its own (IH), and secondary hypersomnia which is usually caused by some other disorder, medication or condition. The exact cause is unknown, but there are cases of people with IH whose family members also have either IH or narcolepsy, so it could be that there is a genetic predisposition to it. In some cases, doctors have noticed abnormal production of a molecule that acts like a sleeping pill, but they still do not know what exactly is inside of that molecule and how it affects people.
There is no FDA approved treatment for IH at the moment, but some people use medications recommended for narcolepsy as it can help. Before the use of polysomnographic studies, IH was often misdiagnosed as narcolepsy. Idiopathic hypersomnia is very similar to narcolepsy, and other types of hypersomnia which all can have a negative impact on people’s job performance, school, social life. Some experts suggest IH should be widely recognized as a disability. Many people who have to live with IH sleep more than 12 hours out of 24, and they can only hope that scientists will find a medication that could control their symptoms.
If you want to help doctors solving the puzzle, you can join the international patient registry which supports research and collects data about patients who have been diagnosed with IH.
The first symptoms of idiopathic hypersomnia occur mostly in adolescence or early twenties, and it can take weeks or months for those symptoms to fully develop. People will notice that they struggle to stay awake and alert during the day and that they fall asleep unintentionally, at inappropriate places and time, which threatens to hinder their daily functioning.
Sleeping longer during the night doesn’t eliminate their sleepiness the next day, and they also struggle with waking up in the morning or after daytime naps. Even after those daytime naps, IH patients don’t feel refreshed or energized. The IH is a chronic disorder, and its symptoms may fluctuate or become more stable over time, but it is hard to predict or control them because it is all very individual.
Here are the main symptoms of idiopathic hypersomnia:
If you recognize any of these symptoms, you should talk to your doctor, depending on the intensity and frequency of symptoms, your doctor will recommend a sleep specialist or a sleep clinic to visit. Your sleep study should be positive on IH if you have these symptoms for at least six months, and if you are not already diagnosed with narcolepsy or post-traumatic hypersomnia.
Researchers are still testing medications for IH, and currently, none is officially approved by the FDA. That is why most people settle with drugs that promote wakefulness and are FDA approved for narcolepsy and use it off-label to alleviate their symptoms enough to function normally.
One of those medications for narcolepsy is modafinil, which is a wake-promoting drug often used among shift workers, patients with sleep apnea and narcolepsy. Modafinil has been used in placebo-controlled studies which included patients with IH, and it has been proved that it helps with sleepiness, however, it does not work for everyone with IH and it some cases its effects fade over time.
Behavioral therapies and scheduled naps may work for narcolepsy, but not for IH. There are a few emerging therapies which include sodium oxybate, clarithromycin, and flumazenil, for those who do not respond to medications.
Besides stimulant medications, people with IH do not have many other options, they simply have to find more time to sleep. It is recommended for them to talk with their friends, family or coworkers and to inform them about their condition and its symptoms so that they know what to expect. Also, they should avoid alcohol and any other medications that can stimulate drowsiness.
Since these two conditions are often mixed, in the chart below, we are going to summarize and compare their main symptoms.
| Symptoms: | Idiopathic hypersomnia | Narcolepsy type 1 | Narcolepsy type 2 |
| Excessive daytime sleepiness | yes | yes | yes |
| Cataplexy | no | yes | no |
| Sleep paralysis and hallucinations | sometimes | yes | sometimes |
| Restorative naps and night sleep | sometimes | yes | sometimes |
| Sleep drunkenness | yes | sometimes | sometimes |
| Troubles with staying asleep during the night | no | yes | sometimes |
According to the doctors, both, IH and narcolepsy are central disorders of hypersomnolence, so they share a few similarities, among which the most important one is excessive daytime sleepiness. When it comes to diagnosis, doctors use overnight sleep studies such as PSG and MSL test to identify these disorders. The number of sleep onset REM periods is the key thing that helps doctors determine which disorder a patient has. SOREMPs are REM periods of sleep which occur within 15 minutes of sleep onset. PSG and MSL tests show that patients who have narcolepsy usually have 2 or more SOREMPs, while patients with IH do not have it at all.
Among other differences is the fact that patients with narcolepsy find brief naps highly refreshing and restorative, while IH patients cannot have a prolonged nap time and they are not feeling much rested after napping.
Cataplexy is a temporary and sudden weakness in muscles, triggered by strong emotions such as laughing or crying, and it is rarely seen outside of narcolepsy, so it is a typical symptom that leaves little to no space for misdiagnosing narcolepsy.
There are many definitions of disability, whether they are financial or physical. All illnesses that are not visible with bare eye face a lot of stigmas, and sometimes it is easier to explain IH as a form of narcolepsy, without going in-depth too much. Another issue is that people with IH are often perceived or labeled as merely lazy, and those prejudices can be harsh because people do not have IH written on their forehead, and even if they did, many would still write it off as something that is not even a real disorder. Many people do not consider it a problem or disability, because who would not love to sleep that much and have a valid excuse for it. But, when you are an adult who needs to work, provide and function you cannot afford yourself a luxury to sleep that much.
Memory issues are common among people with IH, concentration and decision making also suffer, and every basic task requires an extra effort. Everyone can feel cranky and moody when being sleep deprived, but imagine how it is to live in a constant blur and mood swings. Medications and stimulants only work until a certain extent, healthy people sleep at night because there is no such thing as a pill that could replicate the effects of restorative sleep, and the same thing is with IH.
Medications that are currently used for IH cannot repeal the symptoms entirely, so these people have less time during which they can be productive; hence we cannot expect from them to work from 9 to 5. But, there are still options for people with IH who want to work; they can apply for short-term or long-term disability.
If you are dealing with IH, and you are afraid that you might lose your job because of it, do not wait until they write you off completely, but secure your eligibility for disability programs through your employer.
People living with idiopathic hypersomnia feel like all they can do is sleep, all the time, every day. Patients with IH cannot control their condition because although their body got enough restorative sleep time, their brain did not. Their brain is in a state of chronic sleep deprivation, and those people feel like they are always sleep deprived even though they get more sleep than the average person.
Sleep-deprived people would say that those with IH are “blessed” because they do not struggle with falling or staying asleep, but that is just because those two conditions are complete opposites. An even better example of a contrary sleep disorder is insomnia.
One woman living with IH for years described that her symptoms became fully apparent when she was a teen, but she reported that even when she was a baby, her mom could not breastfeed her because she would fall asleep before getting a chance. During her childhood, she was often characterized as lazy, but the truth is that she was always tired, although no one took that seriously. She also highlighted that people with IH are everything except lazy since they have so little time to be productive, they put so much effort into anything because they desperately want to be able to do what everyone else usually does. She reported that getting a diagnose after a sleep study was the best day ever because she finally knew the answer to her problems, and even though it did not actually solve her condition, it was a long-awaited solution.
She would be a morning person if mornings started at noon. Art historian, taurus, coffee lover, traveler, F1 fan who hates to drive, and well experienced insomniac with one life goal, to sleep like a coala for up to 20 hours per day.