What is narcolepsy?
Narcolepsy is a chronic sleep disorder. It causes excessive daytime sleepiness and sudden sleep attacks. The sleep attacks are not controllable and can occur during activities, such as eating or driving. People with narcolepsy may continue these activities while sleeping and not remember when they awaken. This presents a serious risk of physical danger to the person and others around them.
People with narcolepsy can also have a sudden loss of muscle tone that accompanies strong emotion. These attacks—called cataplexy—can be mild or severe and last a few seconds to several minutes. Other characteristics of narcolepsy include sleep paralysis, changes in REM (rapid eye movement) sleep, and hallucinations.
Narcolepsy is relatively rare, affecting about 200,000 Americans. However, experts believe a large portion of people with the disorder remain undiagnosed or are misdiagnosed with another disorder. It typically begins between ages 10 and 30 years and continues for life.
Researchers do not fully understand why narcolepsy occurs. In one form of the disorder, levels of the neurotransmitter, hypocretin, are low or absent. This chemical helps regulate sleep and wakefulness. The reason for this is unclear. It may be due to a combination of genetics and environmental factors. However, most cases of narcolepsy occur in people without a family history of it.
There is no cure for narcolepsy. Narcolepsy treatment uses medications and lifestyle changes to manage excessive daytime sleepiness and cataplexy. Safety precautions are important for managing narcolepsy. Normal daily activities, particularly driving, can be dangerous, especially when cataplexy is present. In fact, some states have restrictions for people with narcolepsy to drive or operate vehicles.
See your doctor if excessive daytime sleepiness, sleep disruptions, or sudden loss of muscle tone occurs. There are several conditions that can mimic narcolepsy. A complete workup and sleep study with narcolepsy test can help your doctor diagnose narcolepsy.
What are the different types of narcolepsy?
There are two types of narcolepsy:
Type 1 narcolepsy is excessive daytime sleepiness with episodes of cataplexy and low levels of hypocretin. It is possible to only have low hypocretin levels and not cataplexy at diagnosis. But eventually, cataplexy will occur in most people with insufficient hypocretin.
- Type 2 narcolepsy is excessive daytime sleepiness without cataplexy or low levels of hypocretin. About 10% of people with type 2 will develop type 1 narcolepsy with either cataplexy or low hypocretin levels.
In rare cases, people develop secondary narcolepsy due to an injury or tumor in areas of the brain that regulate sleep.
What are the symptoms of narcolepsy?
Narcolepsy symptoms usually start in late childhood, adolescence, or young adulthood. Although symptoms are lifelong, they may improve with time and treatment.
Reducing your risk of narcolepsy
The main symptom of narcolepsy is excessive daytime sleepiness. All people with narcolepsy have it. It is persistent sleepiness throughout the day, regardless of how much sleep occurred the previous night. The sleepiness results in sleep attacks where people fall asleep suddenly and uncontrollably. This can happen in the middle of activities including talking and eating. The sleep attack can last a few minutes or up to a half-hour. People awaken feeling refreshed, but then become sleepy again. This is usually the first symptom of narcolepsy and can cause extreme disruptions in a person’s life.
Up to 25% of people with narcolepsy will have all the other symptoms of the disorder. These other symptoms do not necessarily start at the same time as excessive daytime sleepiness. The other symptoms of narcolepsy include:
Automatic behaviors: When people with narcolepsy fall asleep for a few seconds at a time, they can automatically continue whatever activity they are doing. They usually have no recollection of doing the activity and their performance of the activity is impaired. This most often occurs during habitual activities, such as writing or driving.
Cataplexy: This is a sudden loss of muscle tone and voluntary muscle control in response to strong emotion. The emotion is usually positive, such as laughter or excitement. However, negative emotions, such as anger or fear, can also trigger it. The attacks can be mild and only involve a limited group of muscles, such as the eyelids or neck. The attacks can also result in a total body collapse. They can last for just a brief time or up to a couple of minutes. Some people have multiple attacks each day, while others only have a few during their lifetimes. This symptom can mimic a seizure disorder and lead to a misdiagnosis.
Disrupted nighttime sleep: People with narcolepsy typically enter REM sleep within 15 minutes of falling asleep, instead of the normal 60 to 90 minutes. REM sleep is where dream activity takes place. REM sleep can also take place during the day in narcolepsy. These sleep cycle changes can result in fragmented nighttime sleep, vivid dreaming, and acting out during dreams.
Hallucinations: These hallucinations occur as a person is falling asleep or awakening. They are vivid images that people experience as reality because they are not fully asleep or awake. Sleep paralysis can accompany them, making them particularly distressing.
- Sleep paralysis: This is a temporary inability to move or speak while waking up or falling asleep. It mimics the loss of voluntary muscle control everyone has during REM sleep. This normal paralysis keeps you from acting out your dreams. Unlike REM paralysis, in sleep paralysis, people are aware of this immobility because it happens at the edge of sleep. Episodes can last seconds to minutes. People without narcolepsy may also experience this.
Many aspects of narcolepsy can look like other conditions, including mental health problems and other sleep disorders. However, it is far less common than disorders that resemble it. As a result, it can take several years to reach the correct diagnosis. If you have concerning symptoms, consider seeing a sleep disorder specialist for a careful evaluation.
What causes narcolepsy?
Narcolepsy is the result of disruptions in the sleep cycle and pattern. Normally, you fall asleep and enter non-rapid eye movement (NREM) sleep for the first 60 to 90 minutes. Then, your brainwave patterns change and you enter REM sleep where dreaming occurs. In narcolepsy, people can go directly to REM sleep or enter very quickly, within 15 minutes of falling asleep. Many of the symptoms of narcolepsy resemble changes that happen during REM sleep, but they can occur during wakefulness.
The reason for the difference in sleep pattern is unclear. In people with type 1 narcolepsy, doctors know they have low levels of hypocretin. This is a neurotransmitter involved in sleep and wakefulness. Genetics and an autoimmune process may play a role.
What are the risk factors for narcolepsy?
Narcolepsy affects males and females evenly. It most commonly starts between the ages of 10 and 30 years. The main known risk factor for developing narcolepsy is having a family history of the disorder. While most cases occur in people without a family history, your risk of narcolepsy is up to 40 times higher if you have a family member with it.
Reducing your risk of narcolepsy
Unfortunately, it is not possible to prevent or reduce the risk of developing narcolepsy.
What are the diet and nutrition tips for narcolepsy?
There is no specific diet to manage narcolepsy. However, there are changes you can make in what and how you eat and drink that can help with sleep. This includes avoiding the following for several hours before bedtime:
- Large or heavy meals
Ask your healthcare provider for guidance before making significant changes to your diet.
How do doctors diagnose narcolepsy?
To diagnose your condition, your doctor will take a careful and detailed medical history. This may involve keeping a sleep journal for a few weeks and filling out an Epworth Sleepiness Scale. This tool has you rate your chances of dozing off in certain situations to gauge how sleepy you are throughout the day. Your doctor may also ask you several questions including:
What symptoms are you experiencing?
When did you first notice these symptoms?
Do you have these symptoms every day?
How often do you fall asleep during a typical day?
Are you having problems sleeping at night?
What, if anything, seems to make your symptoms better or worse?
- Does anyone in your family have a sleep disorder or similar symptoms?
Your answers to these questions may make your doctor suspicious of narcolepsy. This is especially true if you have cataplexy. Cataplexy is the symptom most specific to narcolepsy. The other symptoms can mimic other sleep disorders or physical or mental health problems.
To make a formal diagnosis of narcolepsy, you will need a sleep study with two specialized tests:
Multiple sleep latency test (MSLT): This test measures the amount of time it takes you to fall asleep during the day. You take five naps throughout the day, with two hours between each nap. Falling asleep in less than eight minutes on average indicates excessive daytime sleepiness. Entering REM sleep in less than 15 minutes on at least two of the naps is a marker of narcolepsy.
- Polysomnogram (PSG): This test takes place overnight in a sleep lab. It measures brain, heart, eye, muscle and breathing activity throughout the night. This information tells your doctor about your sleep cycle and when REM sleep begins. Entering REM sleep in less than 15 minutes is a marker of narcolepsy.
In some cases, doctors may measure levels of hypocretin by taking a sample of CSF (cerebrospinal fluid).
What are the treatments for narcolepsy?
Currently, there is no cure for narcolepsy. However, medications and lifestyle changes can help people with narcolepsy manage their symptoms. Medications doctors use to treat narcolepsy include:
Antidepressants: These drugs can treat cataplexy, hallucinations, and sleep paralysis by suppressing REM sleep. Drug classes include tricyclic antidepressants, such as clomipramine (Anafranil) and imipramine (Tofranil), and SSRIs (selective serotonin reuptake inhibitors) or SNRIs (serotonin and norepinephrine reuptake inhibitors), such as fluoxetine (Prozac) and venlafaxine (Effexor).
Stimulants: These drugs stimulate the central nervous system to treat excessive daytime sleepiness. They are the main treatment for narcolepsy because they promote wakefulness. Modafinil (Provigil) or armodafinil (Nuvigil) are often the first choice because they are less addictive and have fewer side effects than amphetamine-like stimulants. If they are not effective, methylphenidate (Concerta, Ritalin, others) or other amphetamines may be an option.
- Newer stimulants: Two newer stimulants came to market in 2019—pitolisant (Wakix) and solriamfetol (Sunosi). They are non-amphetamine drugs that have similar effectiveness as modafinil.
- Sodium oxybate (Xyrem): This drug is highly effective for cataplexy and helps people with narcolepsy sleep better at night. It is a very strong sedative that you must take at bedtime and then four hours later. Its use is highly restricted due to safety concerns.
Home remedies for narcolepsy
Medications alone may not be able to successfully control narcolepsy symptoms. Lifestyle changes are an important accompaniment to drugs in managing symptoms. Strategies include:
Do not smoke: This is especially important close to bedtime, as nicotine can interfere with sleep.
Exercise every day: Regular moderate-intensity exercise can improve sleep at night and help you feel more awake during the day. Avoid exercising within 4 to 5 hours of bedtime, as this can interfere with sleep.
Keep your room cool: The optimal ambient temperature for sleeping is between 60 and 67°F.
Maintain a regular sleep schedule: You may be able to improve your sleep by going to bed and getting up at the same time every day. This includes weekends.
Relax at night: About an hour before bedtime, do something relaxing to promote sleep. This could include taking a warm bath, listening to music, or reading.
- Take naps: Regularly scheduled naps can help people feel refreshed for up to three hours during the day. In general, naps should be short, around 20 minutes.
Talk with your doctor about your sleep and lifestyle habits for specific recommendations for you.
What are the potential complications of narcolepsy?
Support groups can be a vital resource for people with narcolepsy. They provide an understanding environment and can help you with tips for getting accommodations for your needs. The Americans with Disabilities Act requires employers and school administrators to make reasonable modifications for people with narcolepsy. This includes modifying schedules, allowing for naps, standing, recording meetings and classes, and testing accommodations. You can find more information for students and employees through the Narcolepsy Network.
Narcolepsy can interfere with your emotional, psychological, social and cognitive development. It can lead to difficulties at work or school. Many people with narcolepsy withdraw socially due to unawareness and stigma surrounding the disease. Other potential complications include:
Medical conditions: People with narcolepsy have a higher risk of overweight, obesity, and cardiovascular disease.
Personal relationship problems: Because strong emotion can trigger cataplexy, people with narcolepsy may withdraw emotionally. Avoiding anger or joy may become a way to protect themselves. However, this can interfere with important relationships in their lives.
- Physical harm: Falling asleep during daily activities puts people with narcolepsy at risk of accidents. Some of these situations can be quite serious, such as falling asleep while driving, navigating stairs, or cooking. Because of this, many states name naracolepsy as a condition that may affect a person’s ability to drive or operate vehicles.