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This answer explains the sensation of extremities "falling asleep" as a result of sustained pressure on a nerve. The answer links to an external web page that says that the feeling "quickly goes away once the pressure is relieved."
In my experience, however, it doesn't usually go exactly like this. For me at least, usually what happens is I will start feeling a tingling sensation in my feet after sitting in an awkward position for an extended period of time. If I ignore the sensation for long enough, it continues to get worse until I finally do stand up. But after I stand up, rather than the sensation quickly disappearing, I find that usually it suddenly gets much worse for a period of time. What started as an annoying tingling when I was sitting quickly turns into something quite uncomfortable upon standing up, even to the point where I am not able to walk around properly until the sensation passes a few minutes later.
But once I am standing up, the nerve shouldn't be pinched anymore, so why does the sensation of my foot being "asleep" remain for a few minutes after standing up, and why does it actually seem to briefly get worse after I have already stood up and "unpinched" the nerve?
This paper, while mainly dealing with chronic nerve compression, appears to explain the effects of nerve compression on the blocking the transmission of neural impulses (causing the "sleeping limb" syndrome).
This paper describes how the application of pressure on a nerve causes a miniature case of compartment syndrome, where the pressure causes the intraneuron pressure to increase, leading to paresthesia. Edema also occurs within the neuron, causing pain signals to be sent out. In the experimental rats which were unable to relieve this pressure, permanent nerve damage resulted.
When the effects from the nerve compression exceeds a certain level, the pain/tingling will result in you releasing the pressure from the limb in order to prevent nerve damage.
However, the nerves are still blocked from transmitting their impulses due to the compression blockage described in Paper 1. When the blockage is resolved, the neurons are now capable of transmitting their pain signals, which continue for a period of time until the pressure within the limb falls sufficiently below the pain threshold.
Paresthesia is defined as the abnormal sensation of the skin, such as numbness, tingling, pricking or burning. Paresthesia is a diverse medical condition and the definitions seems too vague. Most of the books define Paresthesia as a symptom of some other disease. Mostly Paresthesia is categorized as transient or permanent. Paresthesia can arise from several causes like artery related, nerve related, migraine, vitamin B deficiency, brain related and may cause from side effects of other drugs.
Classification of transient and chronic Paresthesia is described in detail here.
Nerve impulses require a healthy energy supply, known as the axonal transport system. This well developed micro-vascular distribution method provides the blood flow needed to maintain the cells in good working order. If pressure is put on the correct spot, though, all the tiny arteries, veins and capillaries that supply the nerves' nutrients become pinched off and the nerve cells begin to function abnormally.
Compression isn't the only thing that can cause limbs to fall asleep. Excessive vibration will also lead to paresthesia. Operating hand-held vibrating tools is an extremely common cause of this
As simulation level increases transient Paresthesia may occur, usually disappearing with in a few second
Localized paresthesia or pain occasionally results from a specific mechanism. Mechanical irritation of a peripheral nerve can project such sensations to their periphery.If the pressure on a peripheral nerve provokes paresthesia, then a neuroma or chronic compression occurs. If the pain is initiated by the movement of a joint, there may be a ganglion affected by the process.
Reference : Neurological Differential Diagnosis -- Marco Mumenthaler
The paresthesia mentioned in the question is transient, mostly paresthesia can happen in cold weather conditions or can happen when sitting in a particular position for long time. Several types of paresthesia exist and there are several reasons for the occurrence. But most of them are attributed to the strain in peripheral nerve. When we stand up, the itching effects get increase and it slowly fades out, this is because when the nerve resulted in the formation of paresthesia is stressed more when we take a stand up poster. As some paresthesia is caused by the lack of blood supply, blood supply itself is not always causes paresthesia but there are cases when blood circulation to the nerve is interrupted and this may result in stress of nerve and which may cause paresthesia. These kinds of paresthesia is common and it only last for minutes. So when we stand up the tension to the nerve increases, also the blood pressure increases and blood is slowly available to the nerve. When we try to stand, the nerves are burdened with more tension and paresthesia increases but after sometime the blood flow become natural and paresthesia diminishes slowly. Paresthesia can be reduced by massage or applying pressure on the affected areas, all these are helpful for people having transient paresthesia. Chronic paresthesia and paresthesia due to other medical conditions need more complex treatments.
Causes for paresthesia
Clinical Neurology of the Older Adult -- Joseph I. Sirven, Barbara L. Malamut
Paresthesia and Dysesthesia
According to the post you linked, paresthesia causes the "falling asleep" notion. According to Wikipedia, there are two types of paresthesia, transient and chronic. Transient paresthesia is the type you are describing.
Paresthesias of the hands, feet, legs and arms are common, transient symptoms. The most common, everyday cause is temporary restriction of the blood supply to an area of nerves, commonly caused by leaning or resting on parts of the body such as the legs; other causes include conditions such as hyperventilation syndrome and panic attacks.
Other places like this link mention that parethesia is caused by:
• Obdormition: Obdormition is a numbness caused by prolonged pressure on a nerve, such as when a leg falls asleep if the legs are crossed for a prolonged period. It disappears gradually as the pressure is relieved (1).
• Whiplash: Paresthesias in the upper extremity may occur after whiplash injury (2), a type of cervical soft tissue injury (3). Pujol et al showed that 13% of patients with whiplash had associated paresthesias (4). Recovery usually arises within 6 months after injury (5).
• Hyperventilation syndrome: Paresthesia constitutes 35% of presenting complaints in patients with hyperventilation syndrome (6) and may begin after as little as threeminute of hyperventilation (7). After increasing the depth or frequency of respiration, www.intechopen.com72 Paresthesia the alkaline shift produced selectively increases Na+ conductance and ectopic discharges in normal cutaneous afferent nerves can be induced (8). Other electrolytes, i.e. magnesium, potassium, chloride, phosphate and bicarbonate, also demonstrated significant changes in concentration (7).
• Panic attack: Paresthesiae of the mouth, hands and feet are common, transient symptoms of the related conditions of hyperventilation syndrome and panic attacks. Ietsugu et al demonstrated that paresthesia can be used as a reliable indicator of severe panic attacks (9).
• Transient ischemic attack (TIA): TIA may be manifested by paresthesias. Several reasons may cause TIA such as thrombosis, embolus, intravascular debris and blood vessels disruption. Perez et al. reported the initial manifestation of cardiac myxoma can be paresthesias caused by TIA (10). Post-ischemic paresthesia occurs when hyper polarization by the Na+/K+ pump is transiently halted by elevated extracellular K+. The electrochemical gradient for K+ is reversed and inward transport of K+ triggers regenerative depolarization (8).
• Seizures: Paresthesia may happen during and after a partial seizure (11). Treatment of seizures with vagus nerve stimulation can also trigger paresthesias and is considered an adverse event associated with this treatment modality (12).
• Dehydration: At around 5% to 6% cumulative water loss, paresthesia may occur.
• Insufficient blood supply: Circulatory disorders could lead to transient or chronic paresthesia.
As you can see, there are many causes for paresthesia. The most common is the pressure on the nerves and the loss of loss supply.
Usually, the feeling quickly goes away once the pressure is relieved. But in your case, the paresthesia is delayed because it's caused by restriction of blood flow. Because it is caused by restriction of blood flow, it may take time for the blood the reach the area and oxygenate the nerves.
Why does it get worse? Well, because the action of standing up causes the blood pressure and heart rate to increase, decreasing blood flow to the nerves (read the abstract of this). Another reason is that when standing up, there is increased pressure on the nerves, causing paresthesia. Together, these effects, may increase paresthesia for a few seconds. But when the blood flow becomes normal and the pressure on the nerve decreases, the paresthesia goes away.
There you have it! Nice and concise hopefully… @Daniel if you have more questions, you can ask them by adding a comment to this post.
Hypnic jerks are short, involuntary muscle jerks or twitches that occur right as you are falling asleep. Their involuntary nature makes them a myoclonus, a category of muscles that also includes hiccups. Myoclonic jerks are involuntary muscle twitches that occur quickly, with the muscles immediately returning to relaxation. Hypnic jerks happen randomly, but they always take place while someone is transitioning from wakefulness to sleep.
Hypnic jerks are distinct from the movements associated with sleep disorders like periodic limb movement disorder (PLMD) and restless leg syndrome (RLS). Hypnic jerks occur during the transitionary period between wakefulness and sleep, while RLS symptoms occur before sleep and PLMD movements occur during sleep. Both PLMD and RLS symptoms last longer than hypnic jerks, and typically only only involve the lower legs and feet, while hypnic jerks can affect one side of the body.
What Do Hypnic Jerks Feel Like?
Hypnic jerks can vary in intensity. They could be strong enough to rouse you back to alertness, or they could be so mild that you don’t even notice them. In fact, it’s common to sleep through your hypnic jerks. Some people are only aware they experienced them because their sleep partner told them.
Typically, hypnic jerks only affect one part or side of your body. It’s most common to experience a single hypnic jerk, although several could occur in succession. Often, people experience accompanying sensations with a hypnic jerk. These may include:
- A feeling of falling
- A banging, snapping, or crackling sound
- Visual symptoms like flashing lights, or a dream or hallucination
While less common, people may also report a sensation of pain or tingling.
How Frequently Do Hypnic Jerks Happen?
Around 60 to 70 percent of individuals experience hypnic jerks. Hypnic jerks affect both sexes, and for most people, they occur randomly and sporadically. You can also experience hypnic jerks at any age.
Why Does Type 2 Diabetes Cause Your Feet to Go Numb?
High blood sugar that's uncontrolled can lead to serious complications, like pain, numbness, and injury in the feet and legs.
Numbness in the feet is a symptom of neuropathy or nerve damage, one of the most common long-term complications of type 2 diabetes. Neuropathy is caused by poor blood sugar control that persists over a long period of time.
“The higher the blood sugars and the longer they stay high, the greater the chance of the person developing neuropathy,” says Joel Zonszein, MD, director of the Clinical Diabetes Center at the University Hospital of the Albert Einstein College of Medicine, Montefiore Health System in the Bronx, New York.
“The nerves that get affected by high sugars tend to be the longest nerves in the body,” explains Dr. Zonszein. These nerves go from the spine to the toes, which is why the feet get affected before the arms or hands. Diabetic neuropathy also tends to be bilateral. “Both feet will be affected equally,” he says.
If blood sugar remains poorly controlled, it can lead to serious complications. In the feet, diabetic neuropathy can not only cause numbness but pain and injuries. It can change the shape of your feet, deforming them so they no longer fit into regular shoes. It can also dry out and damage your skin, cause calluses and ulcers on your feet, and interfere with circulation. The numbness also makes it hard to tell if there is a cut or injury which can increase your risk of infections and amputation.
People with diabetes are also at an increased risk for amputation. In 2010, approximately 73,000 non-traumatic lower-limb amputations were performed on adults (20 years or older) diagnosed with diabetes, according to the American Diabetes Association.
The good news is that most amputations are preventable when you manage your diabetes well, take good care of your feet, and wear proper footwear. If you have circulatory problems or you’ve already been diagnosed with neuropathy, you’ll benefit from seeing a podiatrist as well as your endocrinologist.
If you’re concerned you may have neuropathy or if you experience any redness, cracks, pus, ulcers, or other signs of infection in your feet, Zonszein advises going to see your doctor immediately.
The most effective way to prevent or delay diabetic nerve damage is to maintain good control of your blood sugar. Controlling blood pressure and cholesterol is also important. “Lipids [can] have an indirect effect on neuropathy,” says Zonszein.
He also emphasizes the importance of exercise and a healthy diet — and maintaining a healthy weight which will address your overall cardiovascular and cholesterol health. “Patients who are overweight or obese tend to develop more neuropathy and more arthritic problems and pain in their feet because of the [extra] weight,” he adds.
Finally, your doctor may also want to check to make sure you don’t have a vitamin B deficiency. One of the most common medications used to treat diabetes, Metformin, can cause a deficiency in folic acid and vitamin B-12 in about 10 percent of the people who take it, warns Zonszein.
While maintaining good blood sugar control can help prevent or delay neuropathy, there is no cure once the nerves are damaged for a long period of time the medications that are available only treat symptoms and slow the progression of the disease. However, researchers have seen some promising results in recent studies with mice. One published in the July 2015 issue of the Journal of Neurophysiology suggests that fish oil (specifically omega-3 fatty acids) may help reverse or slow the progression of diabetic neuropathy.
Overall, Zonszein says that he has been seeing less and less neuropathy, which he attributes to earlier diagnosis, better treatments, and patients working with their doctors to take charge of the disease. “People with diabetes are doing much better nowadays. We’re seeing complications less often and much later in the disease,” he says. “That’s an important message to patients.”
Parkinson’s & Restless Leg Syndrome: Using Dopaminergic Medication
Because RLS is well-treated by medications that also treat PD, it is likely that some aspect of brain dopamine function is altered in RLS. However, unlike in PD, in which the deficit in substantia nigra dopamine-producing cells can be proven in many ways, no such abnormality has been shown in RLS. For example, studies show that DaTscan results are not abnormal in RLS.
Using dopaminergic medications to treat RLS however can be tricky. In some people they can lead to a phenomenon known as augmentation, in which long term use of dopaminergic medications can worsen the symptoms – making them appear earlier in the day or migrating to the upper body in addition to the legs.
Does having RLS increase the risk of developing PD?
Since RLS affects as much as 4-10% of the US adult population, it is clear that the vast majority of those with RLS do not ever develop PD.
Despite this, it still might be the case that RLS increases the risk of subsequently developing PD. There have been many studies trying to figure this out – with conflicting results. Some studies show that there is no increased risk and others show that having RLS confers about a two-fold increased risk of developing PD over the general population.
Is RLS more common in PD?
But what about the other possibility? Do patients with PD have an increased risk of RLS over the general population? Is it the same RLS as the person without PD has, or is it different? These questions have been difficult to answer. Of course, since PD affects about 1.5% of the elderly, and RLS in about 4-10% of the population, there will be some coincidental overlap. In addition to this however, patients with PD can have sensations that feel like RLS when their dose of dopamine medication is wearing off. These sensations are not truly RLS since they do not have the key features of RLS described above (more common at night, improves with movement, etc) and fluctuate with medication timing, but they can be easily confused with RLS by the person with PD.
Studies of people with PD that assess for RLS and compare to a control group are hindered by the fact that the majority of patients with significant PD are under treatment with medications that affect RLS. Over the years, there have been multiple studies investigating whether RLS is more common in PD than in the general population. Different studies come to different conclusions. Studies conducted in which a group of people with PD are directly compared to a group of people without PD (case-control study) typically show that RLS is more common in PD than the general population.
To complicate matters, some researchers of this topic explain that the experience of people with PD is not actually RLS but rather something else called leg motor restlessness (LMR). The difference between the two is that RLS is worse when the legs are not moving and temporarily relieved by movement whereas leg motor restlessness is not worse when the legs are not moving and not relieved by movement. LMR may be increased in people with PD, whereas true RLS may not be.
Treatment of RLS in PD
Regardless of the above discussion, it is clear that many people with PD have difficulty falling asleep because of annoying sensations in the legs accompanied by a sometimes unbearable sense of restlessness in the legs. For these people, taking dopamine agonists before bed can be helpful. Caution is in order, of course, because in some patients with PD, especially older or more advanced patients, these medications can cause confusion and hallucinations and are thus not well-tolerated. A long-acting levodopa formulation or medications such as gabapentin, gabapentin enacarbil and pregabalin can also be effective. Trying to address sleep issues such as RLS in patients who have sleep complaints can be an important aspect of maximizing therapy for PD.
Tips and Takeaways
- Restless leg syndrome (RLS) causes a feeling of restlessness in the evening hours, usually in the legs, when the limbs are at rest. The restlessness is relieved by movement.
- RLS is a common condition in the general population and may have an increased incidence among people with PD, but studies have been inconsistent.
- Dopamine agonists, levodopa, gabapentin, gabapentin enacarbil, and pregabalin, can be tried to help relieve RLS symptoms, but should be used with caution (as with all medications) due to potential side effects.
- Sleep disorders including RLS are very common in PD and often interfere with getting a restful night sleep. Poor sleep can have significant impacts on your health and wellbeing, so talk with your doctor about these symptoms or any symptoms that interfere with your sleep.
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APDA Vice President and Chief Scientific Officer
Dr. Gilbert received her MD degree at Weill Medical College of Cornell University in New York and her PhD in Cell Biology and Genetics at the Weill Graduate School of Medical Sciences. She then pursued Neurology Residency training as well as Movement Disorders Fellowship training at Columbia Presbyterian Medical Center. Prior to coming to APDA, she was an Associate Professor of Neurology at NYU Langone Medical Center. In this role, she saw movement disorder patients, initiated and directed the NYU Movement Disorders Fellowship, participated in clinical trials and other research initiatives for PD and lectured widely on the disease.
DISCLAIMER: Any medical information disseminated via this blog is solely for the purpose of providing information to the audience, and is not intended as medical advice. Our healthcare professionals cannot recommend treatment or make diagnoses, but can respond to general questions. We encourage you to direct any specific questions to your personal healthcare providers.
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What are some types of balance disorders?
There are more than a dozen different balance disorders. Some of the most common are:
- or positional vertigo: A brief, intense episode of vertigo triggered by a specific change in the position of the head. You might feel as if you're spinning when you bend down to look under something, tilt your head to look up or over your shoulder, or roll over in bed. BPPV occurs when loose otoconia tumble into one of the semicircular canals and affect how the cupula works. This keeps the cupula from flexing properly, sending incorrect information about your head's position to your brain, and causing vertigo. BPPV can result from a head injury, or can develop just from getting older. : An infection or inflammation of the inner ear that causes dizziness and loss of balance. It is often associated with an upper respiratory infection, such as the flu. : Episodes of vertigo, hearing loss, tinnitus (a ringing or buzzing in the ear), and a feeling of fullness in the ear. It may be associated with a change in fluid volume within parts of the labyrinth, but the cause or causes are still unknown. For more information, read the NIDCD fact sheet Ménière's Disease. An inflammation of the vestibular nerve that can be caused by a virus, and primarily causes vertigo. A leakage of inner ear fluid into the middle ear. It causes unsteadiness that usually increases with activity, along with dizziness and nausea. Perilymph fistula can occur after a head injury, dramatic changes in air pressure (such as when scuba diving), physical exertion, ear surgery, or chronic ear infections. Some people are born with perilymph fistula. A feeling of continuously rocking, swaying, or bobbing, typically after an ocean cruise or other sea travel, or even after prolonged running on a treadmill. Usually the symptoms go away within a few hours or days after you reach land or stop using the treadmill. Severe cases, however, can last months or even years, and the cause remains unknown.
Feeling Unsteady? What You Should Know About Balance Problems
You bump into tables all the time. You’ve lost count of the number of times you’ve stubbed your little toe on the doorframe. When you practice yoga, your tree pose looks more like a … fallen tree.
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Are you a little clumsy? Or could your balance problem be something bigger?
Usually, true balance disorders go beyond run-of-the-mill klutziness, says audiologist Julie Honaker, PhD, CCCA, Director of the Vestibular and Balance Disorders Program.
But “balance disorders” include a broad range of problems, from minor lightheadedness to feeling like you’re standing on a boat (on one foot, during a hurricane).
Dr. Honaker shares more about the common causes of balance problems — and how to keep marching steady.
Symptoms of vestibular disorders
The inner ear is the HQ for the body’s balance, or vestibular, system. When something goes awry with that system, a whole range of symptoms can result, including:
- Coordination problems.
- Struggling to walk in a dark room.
- Veering left or right when walking.
- Dizziness or vertigo (a spinning sensation).
- Stumbling or feeling unstable on your feet.
- Sensitivity or difficulty with vision and hearing.
Causes of dizziness
Any number of other things can knock your balance off-kilter, Dr. Honaker says. Something relatively minor, like dehydration or fatigue, can cause a bout of unsteadiness. But what if you’re hydrated, rested — and still stumbling? These are some of the usual suspects.
Medication side effects
Medication is one of the most common culprits of balance problems.
“So often, dizziness is listed as a side effect of medications,” Dr. Honaker points out. If you’re taking multiple prescription meds, they’re even more likely to interact in ways that leave you wobbly.
A virus can infect the ear and derail your sense of balance. Sometimes, colds can cause pressure changes in the middle ear, with the same dizzying effects. These infections usually resolve on their own.
Don’t get too excited — this is less blingy than it sounds. Turns out, we have tiny crystals of calcium carbonate in the inner ear, which play a role in gravity sensing. (Who knew?) Sometimes, the crystals meander into parts of the inner ear where they don’t belong, Dr. Honaker says.
When that happens, you can feel like the room is whirling around you — especially when you move your head suddenly, like rolling over in bed or tipping your head back for a shampoo at the salon. The official name of this disorder is a mouthful: benign paroxysmal positional vertigo. It’s the most common cause of vertigo (and, phew, it’s treatable).
Meniere’s disease causes large amounts of fluid to collect in the inner ear. In addition to dizziness, it can cause hearing problems and ringing in the ears.
The bad news: Meniere’s attacks are unpredictable and may be severe. The good news: You can often manage the disease with diet changes and medication.
You are older and wiser — but perhaps slightly less steady. The inner ear balance system can decline as you age, Dr. Honaker says. Meanwhile, the strength of your eyesight, hearing and even sense of touch can deteriorate — all of which can contribute to poor balance.
But pull on your yoga pants and grab your mat, because balance-boosting exercises like tai chi and yoga can help keep you steady. “It’s important to engage our balance system through regular exercise,” Dr. Honaker says. “If you don’t use it, you lose it.”
When to see a doctor for balance problems
If something seems off with your balance, it’s wise to see a doctor to investigate possible suspects, Dr. Honaker says.
Inner ear problems are often to blame, so definitely mention symptoms such as changes in hearing, ringing or a feeling of fullness in the ears. But sometimes, the problem is related to other issues, such as neurological problems or even heart problems.
Since so many different things can mess with your balance, it makes sense to talk to your primary care doctor first. He or she can help narrow down the suspect list before you visit any specialists.
Many vestibular problems are treatable, Dr. Honaker says, so don’t be afraid to get to the bottom of it.
How to prevent falls
To prevent falls, Dr. Honaker has this advice:
- Get strong. A strong body, particularly your core, will improve your balance and help you avoid falls. Consult a doctor first, but you could try tai chi, yoga or even standard strength training.
- Use handrails. Always use handrails when walking up and down stairs. Falls can happen at any age. Making it a rule to use the handrails could save you from a serious injury.
- Remove hazardous items from the floor. Remove hazardous items from the floor that may trip people, such as stools and scatter rugs.
- Wear low-heeled, flexible shoes with a good tread. For women, it’s tempting to wear high heels, but flats are a safer option if you are worried about losing your balance. For men and women, be sure to wear shoes that have a good tread so you don’t slip on slippery floors.
- Safety-proof your home. Place hand grips in the bath and shower and always use handrails when walking up and down stairs. Use adequate lighting or night lights to safely walk around your home at night.
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**Some foot neuropathies affect the muscle control functions of the involved nerves.
** The muscles of the feet can become weak causing difficulties walking. People with neuropathic foot weakness are typically unable to walk on their tiptoes or heels.
The feet may drag while walking people with this symptom may literally trip over their own feet. Muscle twitches or cramps may also occur.
- Some foot neuropathies affect the muscle control functions of the involved nerves.
- The muscles of the feet can become weak causing difficulties walking.
How Anxiety Causes Numbness
Numbness is an unusual sensation. For some, it's literally the lack of feeling - no amount of touching that area of the body produces any sensations. For others, it's more of a tingling, where the person can feel something there in that area of the body but it doesn't feel like something normally does to the touch.
Talking to a doctor is also useful, especially if the numbness is ongoing. While numbness is associated with some very dangerous diseases, there are some physical causes of numbness, there are some causes that are 100% harmless, and others that may not be physically related.
There’s no cure for narcolepsy. But treatments that can help ease your symptoms include:
- Lifestyle changes: Stay away from caffeine, alcohol and nicotine. Eat smaller meals more often rather than heavy meals. Control your sleep schedule. Schedule daytime naps (10 to 15 minutes long). Follow an exercise and meal schedule.
- Stimulants to treat sleepiness
- Antidepressants to treat problems with REM sleep
- Sodium oxybate (Xyrem, Xywav) to treat cataplexy
- Pitolisant (Wakix) or Solriamfetol (Sunosi) to help you stay awake for longer periods
National Sleep Foundation.
National Organization for Rare Disorders: “Narcolepsy.”
National Institute of Neurological Disorders and Stroke: “Narcolepsy Fact Sheet.”