What is narcolepsy?
Narcolepsy is a sleep disorder that causes an urge to fall asleep suddenly during the daytime that’s almost impossible to resist. Although this condition isn’t common, it’s widely known because of its symptoms and how they happen. Narcolepsy is usually treatable, but the condition can still cause severe disruptions in your life, ability to work and social relationships.
What are the symptoms of narcolepsy?
There are four main symptoms of narcolepsy, but most people with this condition don’t have all four. The four symptoms are:
- Excessive daytime sleepiness. This symptom happens to everyone with narcolepsy. People with narcolepsy and experts on the condition often describe these as “sleep attacks.”
- Sudden muscle weakness (cataplexy). This can have mild effects, affecting one side of your body or only light muscle weakness. (See below for more about this symptom.)
- Sleep-related hallucinations. These happen right after falling asleep or right before waking up.
- Sleep paralysis. When you have this symptom, you’ll wake up — sometimes fully, but not always — but find yourself unable to move. (See below for more about this symptom.)
More about cataplexy
There are two main types of narcolepsy, and whether or not you have cataplexy separates the two. The two types are:
- Narcolepsy type 1: This form involves cataplexy. About 20% of narcolepsy cases are type 1.
- Narcolepsy type 2: This form doesn’t involve cataplexy. The majority of narcolepsy cases — about 80% — are type 2.
Under ordinary circumstances, your brain shuts down most muscle control in your body to keep you from acting out your dreams. People with cataplexy will have sudden muscle weakness, similar to how your body blocks movements during REM sleep.
Mild cataplexy may only affect your face and neck — such as your jaw dropping involuntarily — or just one side of your body. Severe cataplexy can make you collapse to the ground, which can lead to injuries. These events usually last under a few minutes, but you may not be able to move or talk at all during that time.
Cataplexy is also unusual because certain emotions cause it to happen. Positive emotions are most likely to trigger cataplexy, especially laughing, making jokes or other humor-related behavior. Surprise, fear and anger can also trigger cataplexy, but aren’t as likely to do so.
Cataplexy can take slightly different forms in children and in people whose symptoms started within the past six months. For them, cataplexy can look like sudden, uncontrollable grimacing or face-scrunching, sticking out their tongue or loss of muscle tone (making muscles feel soft and limbs “floppy”) throughout their body without an emotion-related cause.
More about sleep paralysis
Your brain shuts down muscle control in your body to keep you from acting out your dreams, but this should end when you wake up. However, if you have sleep paralysis, your body doesn’t regain muscle control as it should. You can still breathe and move your eyes, but you can’t talk or move the rest of your body.
Hallucinations during sleep paralysis are very common, and they’re often vivid and extraordinarily frightening. Fortunately, sleep paralysis is usually very short-lived, lasting only a couple of minutes at most (though people with this often describe that it feels longer).
In addition to the four main symptoms, some other symptoms or behaviors are common in people with narcolepsy. Some of the more common or easily noticeable behaviors include:
- Automatic movements. People with narcolepsy can often fall asleep, but may keep moving parts of their body like their hands.
- Amnesia or forgetfulness. It’s common for people with this condition to not remember what they were doing right before falling asleep.
- Sudden outbursts around sleep attacks. A person with narcolepsy may suddenly speak up and say something (usually words or phrases that are nonsensical or unrelated to what’s happening around them). When someone with narcolepsy does this, it might startle them back to being fully awake, but most people who do this also don’t remember doing it.
Who does narcolepsy affect?
Healthcare providers usually diagnose narcolepsy in people between the ages of 5 and 50. However, it’s most likely to appear in young adults in their late teens and early 20s. Men and people assigned male at birth (AMAB) have a higher risk of developing narcolepsy.
How common is narcolepsy?
Narcolepsy is uncommon. Available research shows that it affects 25 to 50 people out of every 100,000 worldwide. However, this condition often takes years to diagnose, so the actual number of people with it is difficult to estimate.
How does narcolepsy affect my body?
To understand narcolepsy, it helps to know more about the way the human sleep cycle works. That cycle involves the following stages:
- Stage 1: Light sleep. This short stage begins right after you fall asleep and accounts for about 5% of your total sleep time.
- Stage 2: Deeper sleep. This stage is deeper and makes up about 45% to 50% of all the time you spend sleeping (this number goes up as you get older).
- Stage 3: Slow wave sleep. This stage makes up about 25% of the time you spend sleeping (this number goes down with age). It’s very hard to wake someone up in stage 3 sleep, and waking up directly from it usually causes “sleep inertia,” a state of “mental fog” and slowed thinking. This is also the stage where sleepwalking or sleeptalking typically happens.
- REM sleep: REM stands for “rapid eye movement.” This stage is when you dream. When a person is in REM sleep, you can see their eyes moving beneath their eyelids.
If you don’t have narcolepsy, you typically enter stage 1 when you fall asleep and then move into stages 2 and 3. You’ll cycle between these stages and ultimately go into REM sleep and start dreaming. After the first REM cycle, you start a new cycle and go back into stage 1 or 2. One cycle normally takes about 90 minutes before another begins. Most people go through four or five cycles per night (assuming they get a full eight hours).
If you have narcolepsy, your sleep cycle doesn’t happen like that. Instead, you’ll go into the REM stage shortly after falling asleep. The rest of the night, you’ll sleep only in short stretches, often without going through the typical sleep cycle.
With narcolepsy, no matter how well you sleep at night, you’ll feel extremely sleepy during the daytime. That urge to fall asleep is usually impossible to resist, but these sleep periods are also short (about 15 to 30 minutes) during the day. Once you wake up, you’ll feel rested and ready to resume whatever you were doing before. However, this happens several times during the day, which is why narcolepsy is so disruptive.
Symptoms and Causes
What causes narcolepsy?
The causes of narcolepsy depend on the type of narcolepsy itself. However, they all have links to your hypothalamus, a specific area in your brain that helps regulate your sleep and wake times.
Type 1 narcolepsy
In 1998, researchers discovered orexins, a type of chemical molecule created and used by certain neurons (brain cells) for communication. The neurons that use orexins are in a part of your brain called the hypothalamus, and those neurons are key to how you stay awake.
Orexin (sometimes called hypocretins) is a molecule produced by neurons that’s usually detectable in cerebrospinal fluid (CSF), a thin layer of fluid surrounding and cushioning your brain and spinal cord. However, CSF levels of orexin are very low — or undetectable — in people with narcolepsy. That means the cells that make orexin either stopped working or something destroyed them.
According to further research, the most likely reason those neurons stopped working is an autoimmune problem. That means your immune system attacked the neurons that make and use orexins, the orexins themselves or both.
About 90% to 95% of people with type 1 narcolepsy have a specific genetic mutation (the identifier for this mutation is HLA-DQB1*06:02) that affects their immune system. However, about 25% of all people also have this mutation but don’t have narcolepsy. As a result, experts rarely test for this mutation and they aren’t certain what role it plays. There’s also some evidence that this condition runs in families, as having a first-degree relative (a parent, sibling or child) with narcolepsy puts you at higher risk for developing it.
However, people can also develop type 1 narcolepsy after certain viral and bacterial infections, especially strains of H1N1 influenza and bacteria like those that cause strep throat. Experts suspect that’s because infections can sometimes trigger changes and malfunctions in your immune system.
Type 2 narcolepsy
While experts know much of why type 1 narcolepsy happens, that’s not the case with type 2 narcolepsy. Experts still don’t fully understand why type 2 narcolepsy happens. But they suspect it happens for similar reasons. Those include less-severe loss of the neurons that use orexin or a problem with how orexin travels in your brain.
In rare cases, narcolepsy can happen because of damage to your hypothalamus. You can have this kind of damage from head injuries (such as concussions and traumatic brain injuries), strokes, brain tumors and other conditions.
Narcolepsy can also happen as a feature of unrelated conditions that you can inherit. Examples of this include:
- Autosomal dominant cerebellar ataxia, narcolepsy and deafness (ADCADN).
- Autosomal dominant narcolepsy, type 2 diabetes and obesity.
Is narcolepsy contagious?
Narcolepsy isn’t contagious. You can’t spread it to or catch it from others.
Diagnosis and Tests
How is narcolepsy diagnosed?
A healthcare provider can suspect narcolepsy based on your symptoms. However, narcolepsy shares symptoms with several other brain- and sleep-related conditions. Because of that, the only way to diagnose narcolepsy conclusively is with specialized diagnostic tests.
Before doing most of the main tests for narcolepsy, a healthcare provider will first make sure that you’re getting enough sleep. That usually involves simple tracking methods for your sleep-wake patterns, such as actigraphy. This typically uses a watch-like device that you wear on your wrist to track movement patterns (such as when you’re sleeping vs. when you’re up and moving around while awake).
What tests will be done to diagnose narcolepsy?
Some possible tests for diagnosing narcolepsy include:
- Sleep study (polysomnogram).
- Multiple sleep latency test (MSLT).
- Maintenance of wakefulness test.
- Spinal tap (lumbar puncture).
Sleep study (polysomnogram)
A sleep study involves multiple types of sensors that track how you sleep. A key part of a full sleep study, formally known as a polysomnogram, is that it includes electroencephalogram (EEG) sensors. Those sensors track your brain waves, allowing healthcare providers to see what stage of sleep you’re in from minute to minute.
A sleep study can help diagnose narcolepsy because people who have this condition go into the REM stage sleep unusually fast compared to people who don’t. They’ll also have sleep broken up by periods of wakefulness, which the sleep study can also detect and record.
Another key reason why a sleep study is necessary is that excessive daytime sleepiness is also a main symptom of sleep apnea. A sleep study can rule out sleep apnea.
Multiple sleep latency test
This test involves testing whether or not you’re prone to falling asleep during the daytime. This test involves timed naps that happen in a specific timeframe. This test can help determine if a person has excessive daytime sleepiness, which is a required symptom of narcolepsy. This test often happens the following day after an overnight sleep study.
Maintenance of wakefulness test
This test determines if you can stay awake during the daytime, even in situations where it would be easy to fall asleep. While it’s not common in testing for narcolepsy, it’s still possible and can rule out other issues. It’s also useful for testing if stimulant treatments are helping.
Spinal tap (lumbar puncture)
This test can help determine if the orexin levels in your CSF are low. This is a key way to diagnose type 1 narcolepsy. Low orexin levels can also signal that someone with narcolepsy may develop cataplexy, even if they haven’t yet shown that symptom. Unfortunately, orexin levels don’t change in people with type 2 narcolepsy, so it isn’t always a test that helps with diagnosis.
Many other tests are also common for people who have narcolepsy. An example of why this might happen is having cataplexy as a symptom. Cataplexy is similar to several other motor (movement-related) symptoms of brain conditions, such as atonic seizures (also known as drop attacks).
Because of that, healthcare providers might first test for more severe conditions like seizures and epilepsy, which means narcolepsy may take longer for providers to pinpoint and diagnose. Other tests are possible, too, and your healthcare provider is the best person to explain what tests they recommend and why.
Management and Treatment
How is narcolepsy treated, and is there a cure?
Narcolepsy is treatable but not curable. Treatments usually start with medications, but changes to your daily routine and lifestyle can also help. In general, narcolepsy responds well to treatment, which helps limit the disruptions that symptoms can cause.
What medications or treatments are used to treat narcolepsy?
Medication is the main method for treating narcolepsy. Most medications target excessive daytime sleepiness, but some target other symptoms, too. Possible medications for this condition include:
- Wakefulness medications. These are usually the first line of treatment. Examples of these drugs include modafinil and armodafinil. These medications stimulate your nervous system, which can help reduce the severity or frequency of daytime sleepiness.
- Amphetamines and amphetamine-like stimulants. Drugs like methylphenidate (better known under several trade names, including Ritalin®, Concerta® or Qullivant®) or amphetamine/dextroamphetamine combinations (better known by the trade name Adderall®).
- Antidepressants. Medications like serotonin-norepinephrine reuptake inhibitors (SNRIs) such as venlafaxine (commonly known by the trade name Effexor®), selective serotonin reuptake inhibitors (SSRIs) like fluoxetine (better known under the trade name Prozac®), or tricyclic antidepressants like clomipramine or protriptyline (but these are less common).
- Sodium oxybate. This drug can help you sleep and also reduces how often cataplexy happens. Most countries control this drug very tightly because of its effects, but it’s still used frequently for treating type 1 narcolepsy.
- Histamine-affecting drugs. An example of this type of drug is pitolisant, a histamine receptor antagonist. Receptor antagonists are drugs that block specific chemicals in your body from attaching to cells. That slows down or prevents the cells from doing certain things.
While there are multiple treatment options for narcolepsy in adults, treatment options in children are very limited. Your child’s pediatrician or a specialist provider is the best person to tell you what treatment options are available or what they recommend.
Complications/side effects of narcolepsy treatment
Many medications that treat narcolepsy or its symptoms are more likely to interact with other drugs. High blood pressure (hypertension) and irregular heart rhythms are just two possible complications with stimulant medications of any kind. Sodium oxybate in particular is dangerous if combined with other drugs that dampen how your central nervous system works, and you should never mix it with alcohol.
In general, your healthcare provider is the best person to tell you what side effects, complications or medication interactions to watch for or avoid. They can tailor the information to your specific case and situation, accounting for your health history and personal circumstances.
How do I take care of myself or manage my symptoms?
You shouldn’t try to self-diagnose and self-treat narcolepsy. That’s because the symptoms of this condition happen commonly with other conditions like sleep apnea or epilepsy, which are also dangerous. This condition can also make certain activities like driving or swimming dangerous, so you should always see a healthcare provider for diagnosis and treatment.
How soon after treatment will I feel better, and how long does it take to recover from this treatment?
The recovery time or time to feel the effects of treatments for narcolepsy depends on many factors. Your healthcare provider is the best person to tell you what to expect in your case, including the timeline on when you should see the effects of medications or changes in your symptoms.
How can I reduce my risk or prevent narcolepsy?
Narcolepsy happens unpredictably in almost all cases. Because of that, it’s impossible to reduce your risk of developing it or prevent it from happening.
Outlook / Prognosis
What can I expect if I have narcolepsy?
Narcolepsy isn’t usually dangerous on its own, but the sudden, irresistible need to sleep is very disruptive. People with this condition may be unable to drive (either temporarily or permanently, depending on their specific symptoms and circumstances).
While narcolepsy usually isn’t dangerous, type 1 narcolepsy does have added risks of injury from falls when cataplexy is severe. Narcolepsy can also create dangerous situations when driving, using power tools or heavy equipment, swimming and more.
Narcolepsy in children
Children with narcolepsy often struggle because of the effects of the condition. Daytime sleepiness can make it hard to pay attention in school, maintain social relationships and participate in school and non-school activities.
However, narcolepsy is a medical condition. Because of this, children with narcolepsy often have legal protections, and the law requires schools to provide suitable accommodations. Some examples include adjusting class schedules, having time built in time for naps or rest periods and taking medications while at school. Your child’s pediatrician or other experts can help you navigate this and find solutions that can help your child.
Narcolepsy in working adults
Much like the legal protections for children in schools, adults with narcolepsy also commonly have legal protections because of this condition. The Americans with Disabilities Act prohibits discriminating against someone because of a medical condition (including narcolepsy) in the United States.
That legal protection means people with narcolepsy can often work out accommodations agreements with their employers to make it possible for them to have a career while still managing their condition.
How long does narcolepsy last?
Narcolepsy is permanent once you develop it, so it’s a lifelong condition. However, it doesn't get worse over time.
What is the outlook for narcolepsy?
Narcolepsy isn’t dangerous on its own, but it can make it hard to go to certain places or do certain activities. It also can disrupt going to school, having a job and other common parts of your life. While treatment isn’t always totally effective, most cases of narcolepsy respond to treatment. That means you can usually manage this condition and limit how it affects your life.
How do I take care of myself?
If you have narcolepsy, there are several things you can do to help manage your condition and make treatments more effective. Most of these relate to practicing good sleep hygiene or otherwise adjusting your schedule and routine, including the following actions:
- Be consistent with your sleep habits. Sticking to a sleep schedule can improve how well you sleep.
- Make time for sleep. Set a bedtime that allows you to get the recommended amount of sleep for your age. You should also build some time into your schedule before going to sleep to wind down and relax.
- Limit the time you spend around bright lights or using electronics. Light from these too close to bedtime can disrupt your body’s natural sleep-wake functions.
- Avoid drinking alcohol or caffeine, using tobacco or eating a meal too close to bedtime. A light snack is the best option if you feel hungry before bedtime. You should avoid alcohol entirely if you take certain medications (your healthcare provider can tell you if they prescribe any of these for you). Experts also strongly recommend quitting tobacco products entirely (including vaping and smokeless tobacco).
- Be physically active. Staying active, even just going for a walk, can help with the quality of your sleep.
- Have a nap. People with narcolepsy will often feel better after taking a short nap. Once you figure out the times of day you feel sleepiest, adjusting your schedule to nap at those times can help you.
Avoid dangerous activities or take precautions when you do them
Narcolepsy can — and does — lead to serious or even deadly auto crashes. To keep yourself and those around you safe, you should never drive unless a healthcare provider specifically clears you to drive.
If you notice that narcolepsy symptoms are happening while you’re driving, you should stop driving entirely and contact your healthcare provider. While this is inconvenient even in the best of cases, it’s also crucial to avoiding deadly or life-changing consequences of a car crash because you fell asleep behind the wheel.
Another key area where narcolepsy creates a specific danger is in the water. If you have narcolepsy, it’s very important that you always wear a life preserver when swimming or are in any kind of boat or watercraft where a life preserver is recommended. Without a life preserver or lifejacket — worn properly at all times — a sleep attack in the water could have deadly consequences.
When should I see my healthcare provider?
Falling asleep suddenly without an expected reason is a sign that you need to see a healthcare provider. All of these are symptoms of many conditions, not just narcolepsy, and several of those conditions are severe. With many of these conditions, the longer you wait to get a diagnosis and treatment, the more likely you’ll face complications or that treatment will be less effective.
When should I go to the ER?
You should seek medical care at a hospital or emergency room if you collapse or pass out unexpectedly. This is a key symptom of many conditions, including heart attack, stroke, irregular heart rhythms and more. Those conditions are medical emergencies and need immediate care.
Collapsing or passing out unexpectedly also puts you at risk for fall-related injuries. You should always get medical attention if you have a possible injury to your head, neck or any part of your back and spine. Fractures and injuries to your spinal cord at any level can cause permanent damage, paralysis or even death.
You should also get medical attention if you fall and you’re taking blood-thinning medications of any kind, especially if you hit your head. Falls and injuries create a risk for dangerous internal bleeding, and you need medical attention to make sure you don’t have injuries that could lead to deadly complications.
A note from Cleveland Clinic
Narcolepsy is a brain-related condition that causes disruptions in your body’s natural sleep/wake processes. While this condition isn’t usually dangerous directly, it can create risks in certain situations. It’s also a condition that can seriously disrupt your life, routine and activities. Many people with this condition may have issues with routine activities like working and driving.
Fortunately, this condition is treatable, and most people with narcolepsy see at least some improvements from treatment. Adjusting sleep-related behaviors can also help. While it’s not always possible to prevent the symptoms of narcolepsy, many people can manage this condition and adapt to most — if not all — of its effects.
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