Key Takeaways

  • Narcolepsy is a sleep disorder affecting an estimated 126,000 people in the United States, but the true number may be higher due to underdiagnosis and similarities to other conditions.
  • Symptoms of narcolepsy include excessive daytime sleepiness and disrupted nighttime sleep, sometimes accompanied by cataplexy, which is muscle weakness triggered by strong emotions.
  • While there is no cure for narcolepsy, treatments and lifestyle adaptations, such as sleep hygiene, scheduled naps, exercise, and avoiding certain substances, can help manage the symptoms.

Narcolepsy is a relatively rare sleep disorder that causes a person to feel sleepy or fall asleep suddenly during the daytime hours. As of 2023, around 126,000 people in the United States were reported to have narcolepsy, although the true number may be higher.

This neurological condition is difficult to diagnose because it shares features with other disorders. Researchers believe narcolepsy may be underdiagnosed.

The true prevalence of narcolepsy isn’t known and may vary from region to region. Researchers suspect the condition is underdiagnosed or sometimes misdiagnosed as other medical conditions.

Conditions that may be either confused or comorbid (occurring together) with narcolepsy include:

The Nexus Narcolepsy Registry is an online, patient-led registry that collects information on medically diagnosed narcolepsy from adults. Based on this data, the prevalence of narcolepsy is highest among white females, but other populations may be underrepresented.

The National Organization for Rare Disorders reports that around 1 in every 2,000 people may have narcolepsy. Other researchers estimate that approximately 20 to 55 per 100,000 people worldwide may live with the condition.

In some countries, this number may be higher or lower. Some researchers point to a gap in data between reporting of white and European cases versus those in other populations.

Do you nod off at random points throughout the day? Do you also have trouble sleeping through the night?

If you suspect you have narcolepsy, you may experience symptoms including:

  • Daytime sleepiness. Excessive daytime sleepiness (EDS) is the kind of sleepiness that causes someone to fall asleep frequently when they don’t want to — at the wrong time and place. People may also experience sudden sleep episodes, often called sleep attacks.
  • Rapid eye movement (REM) sleep changes. REM is a state of sleep during which the eyes move rapidly. People with narcolepsy may quickly slip into REM sleep cycles even during the day.
  • Sleep paralysis. As a person awakens from REM sleep, there may be a few seconds to minutes when they’re unable to speak or move their body. Some people with narcolepsy have this symptom frequently, some not at all.
  • Hallucinations. Some people may experience vivid, sometimes disturbing, dream-like images either when falling asleep or waking up. Usually, hallucinations are visual, but they may also involve touch, smell, and other senses.
  • Cataplexy. This symptom, which not all people with narcolepsy experience, involves a sudden loss of muscle tone. This may be subtle, with loss of facial or hand muscle tone, or it may affect many muscle groups, leading a person to fall to the ground. Unlike sleep paralysis, cataplexy happens when a person is fully awake. It’s often triggered by strong emotions (laughter, anger, fear, excitement, etc.).
  • Nighttime sleep disruption. People with narcolepsy may also have trouble falling and staying asleep at night. They may experience vivid dreams, sleep apnea, insomnia, or sleep-related movements, such as acting out and leg movements.
  • Automatic behavior. If sleep episodes are very brief, people may continue doing habitual activities, such as brushing teeth or driving. They may also put things in drawers where they don’t belong and write illegibly.

The symptoms of narcolepsy can overlap with other conditions. For example, a person may have excessive daytime sleepiness if they’ve had a head injury or are taking certain medications.

Cataplexy may also sometimes be confused with drop attacks or seizures from epilepsy.

People can have one of several forms of narcolepsy, including:

  • type 1 narcolepsy (formerly called narcolepsy with cataplexy)
  • type 2 narcolepsy (formerly called narcolepsy without cataplexy)
  • as a result of a brain injury, or lesion in the brain (secondary narcolepsy)

With cataplexy, a person experiences muscle weakness, particularly in response to strong emotions. This means their body, or parts of it, may go limp without warning. They may lose control of their muscles or be unable to move during episodes lasting from a few seconds to around 2 minutes.

People with cataplexy have low levels of a brain chemical called hypocretin. It’s this marker that can help with diagnosis, as cataplexy is not a feature of similar disorders.

Scientists estimate that somewhere around 14 per 100,000 people have type 1 narcolepsy (with cataplexy).

Researchers continue to work on learning the cause of narcolepsy.

Currently, many researchers believe that the following causes are possible:

  • Low hypocretin levels. People who have type 1 narcolepsy may have very low hypocretin levels. People who have type 2 narcolepsy (without cataplexy) generally have the expected hypocretin levels.
  • Autoimmune disorders. If you have an autoimmune disorder, your immune system may attack healthy parts of your body (cells, tissues, etc.). This may affect how much hypocretin your body produces. It is also why, now, scientists believe type 1 narcolepsy is an autoimmune disease.
  • Family history. Narcolepsy does not typically run in families. Most cases of narcolepsy are sporadic (occurring at random). However, some clusters are seen in some family groups.
  • Brain injury or issue. In rare cases, a brain injury may lead to narcolepsy. After an injury, the part of the brain that regulates REM sleep may not function as expected. This may also be the case if you have a brain tumor or another condition affecting the brain.
  • Other triggers. Other possible triggers may include psychological stress and certain infections.

It may take up to 10 years after symptoms appear to get a confirmed diagnosis of narcolepsy.

Researchers suggest that symptoms typically start between the ages of 7 and 25. Symptoms may start out mild but become more noticeable with age. Eventually, the symptoms stabilize over many years.

At your appointment, a doctor will ask about your sleep symptoms and medical or family history. From there, you may be asked to do the following:

  • Log your symptoms. The doctor may ask you to keep a log of daytime and nighttime sleep. It’s important to note cataplexy because it can be a specific symptom of type 1 narcolepsy.
  • Have an overnight sleep study. Also called a polysomnography (PSG), a sleep study is usually performed in a lab setting. The doctor will monitor your breathing, brain, and muscle activity, as well as your REM sleep patterns, to rule out other conditions such as sleep apnea or movement disorders. People with narcolepsy may enter REM sleep in less than 15 minutes.
  • Have a multiple sleep latency test (MSLT). An MSLT measures how quickly you can fall asleep during the day and enter a REM cycle. Unlike during a sleep study, where you’re asked to sleep normally through the night, in an MSLT, you’re asked to take short naps a couple of hours apart (4 to 5 times) during the day. Falling into REM within 15 minutes in at least two of the five naps is a marker for narcolepsy.
  • Try other tests. The doctor can also test your cerebrospinal fluid (CSF) for hypocretin. They will obtain a CSF sample through a spinal tap, also known as a lumbar puncture. However, this is rarely required for diagnosis.

Narcolepsy is a lifelong condition. Treatments can help with the symptoms, but there’s currently no cure.

Treatments include:

  • Wake-promoting agents. Modafinil or armodafinil promotes wakefulness and alertness. Methylphenidate is an amphetamine-like stimulant that also promotes wakefulness, but may have more side effects and addictive properties. More recently, pitolisant (Wakix) and solriamfetol (Sunosi) have been introduced.
  • Antidepressants. Tricyclic antidepressants (TCAs) or serotonin-norepinephrine reuptake inhibitors (SNRIs) may help control episodes of cataplexy.
  • Sedatives. Sodium oxybate (gamma hydroxybutyrate or GHB) can be taken at night to help with both cataplexy and daytime sleepiness.

Lifestyle modifications, such as practicing good sleep hygiene habits and taking brief, scheduled naps (e.g., after lunch or later in the afternoon), are other options. Exercising daily and avoiding caffeine, alcohol, and nicotine may also make nighttime sleep more restful and help reduce daytime sleepiness.

You may also ask a doctor about local support groups for people with narcolepsy. Online support is also available at places like the Narcolepsy Network or Rare Connect’s Narcolepsy Community.

While narcolepsy is rare, it’s also difficult to diagnose. The sooner you seek a diagnosis, the sooner you may find help for whatever sleep difficulties you’re experiencing.

If you do have narcolepsy, a doctor can help you find the appropriate treatments, lifestyle modifications, and support groups to help you live your best life.