Insomnia is a common sleep disorder characterized by the inability to go to sleep or stay asleep. Insomnia can be acute (short term) or chronic (long term).

Narcolepsy, on the other hand, is considered a rare, chronic neurological sleep disorder. Narcolepsy is characterized by severe bouts of daytime drowsiness and other symptoms, including insomnia.

This article will take a closer look at the differences between insomnia and narcolepsy, the potential link between the two conditions, as well as the causes and symptoms of each.

Insomnia is very common. Approximately 1 in 4 U.S. adults develop acute (temporary) or chronic (long term) insomnia every year.

But unlike insomnia, narcolepsy is rare. Narcolepsy affects anywhere from 135,000 to 200,000 people in the United States. And since this condition is underdiagnosed, that estimate may be low. But even taking underdiagnosis into account, narcolepsy is much less common than insomnia.

Both conditions have multiple causes. Research suggests that for some people, an imbalance in the production of hypocretin (or orexin), a brain chemical, may be an underlying cause for both.

NarcolepsyInsomnia
Causesnot always known

includes conditions that kill off the brain cells that produce orexin

family history of this disease is a risk factor
poor nighttime habits

emotions, including worry and stress

use or overuse of substances like nicotine, alcohol, and caffeine
Symptomsinsomnia and fragmented sleep

severe daytime sleepiness

cataplexy (in type 1)

hallucinations

sleep paralysis
trouble falling or staying asleep

early wakefulness

daytime exhaustion and irritability caused by lack of sleep

The main difference between narcolepsy and insomnia is their frequency of occurrence in the population. The symptoms and treatments of each also differ.

Causes of narcolepsy

Narcolepsy is a neurological disorder that alters the brain’s ability to control the sleep-wake cycle. People with narcolepsy may have insomnia as a symptom.

The two major types of narcolepsy are:

  • Narcolepsy type 1. People with type 1 narcolepsy have low levels of orexin (hypocretin), a brain chemical that regulates wakefulness. Damage to the brain cells that produce this chemical may cause it. Narcolepsy type 1 is characterized by a symptom called cataplexy. This condition was formerly known as narcolepsy with cataplexy.
  • Narcolepsy type 2. People with type 2 narcolepsy have normal levels of orexin. Cataplexy is not a symptom of type 2. This condition was formerly known as narcolepsy without cataplexy.

The exact cause of narcolepsy is not completely understood. Data reported by the National Institutes of Health (NIH) indicates that certain risk factors may damage or eradicate the brain cells that produce orexin, including:

  • Autoimmune conditions. Autoimmune conditions may cause the immune system to attack the brain cells that contain orexin.
  • Traumatic brain injury. Injuries to the hypothalamus, which regulates wakefulness and REM sleep, is a less common cause. Narcolepsy caused by a brain injury is referred to as secondary narcolepsy.
  • Tumors or illnesses. Other conditions can affect the hypothalamus too.

Having a family history of narcolepsy is also a risk factor.

Causes of insomnia

Insomnia does not cause narcolepsy or narcolepsy symptoms.

A wide range of lifestyle factors and health conditions can cause insomnia, including:

  • poor sleep hygiene and nighttime habits, such as late-night computer use
  • emotions such as stress, worry, and anxiety
  • alcohol or drug use
  • nicotine use
  • caffeine
  • sleep apnea
  • gastroesophageal reflux disease (GERD)
  • restless leg syndrome
  • medications, including some antidepressants and blood pressure medications

Narcolepsy and insomnia have some symptoms that overlap, but they are significantly different in the way they present and have different causes.

Symptoms of narcolepsy

Narcolepsy symptoms include:

  • Severe, extreme daytime sleepiness. This can occur even after a good night’s sleep. These episodes are sometimes referred to as sleep attacks. They differ from the tiredness and fatigue caused by insomnia.
  • Cataplexy (in type 1). Cataplexy is a sudden loss of muscle tone that leads to bodily weakness and the loss of voluntary muscle control. Cataplexy occurs during periods of wakefulness. Intense emotions often trigger it.
  • Sleep paralysis. Symptoms include temporary inability to speak or move when falling asleep or waking up. Episodes last for seconds or minutes.
  • Hallucinations. Vivid, imaginary imagery that may be frightening can accompany sleep paralysis. These hallucinations can have an auditory component.
  • Insomnia and fragmented sleep. Trouble falling and staying asleep is common in people with narcolepsy.

Symptoms of insomnia

The main symptoms of insomnia include:

  • trouble falling asleep
  • difficulty staying asleep
  • waking up too early
  • daytime fatigue and irritability
  • trouble concentrating during the day
  • problems with memory caused by lack of sleep

Narcolepsy and insomnia have both been linked to the same chemical in the brain: hypocretin (also called orexin).

Hypocretin is a naturally occurring chemical peptide that is mainly produced in the hypothalamus. This chemical plays a key role in the regulation of sleep and mood.

People with a diagnosis of narcolepsy type 1 have very low levels of hypocretin in their brains. On the opposite end of the spectrum, some people with insomnia may produce too much hypocretin.

Although people with narcolepsy produce too little hypocretin and are sleepy during the daytime, they often also have trouble staying asleep at night. They may experience fragmented sleep at night due to:

Narcolepsy is sometimes misdiagnosed as hypersomnia. Hypersomnia is another condition that causes extreme daytime drowsiness and sleep attacks.

Narcolepsy may cause hypersomnia-like symptoms. But people with hypersomnia do not experience cataplexy. The cause of hypersomnia is not known.

Other conditions that can cause excessive sleepiness during the day include:

You can manage the symptoms of these sleep conditions. Here are treatment options to consider.

Insomnia treatments

Insomnia often resolves when the underlying cause is reduced or removed.

If falling asleep is difficult, try altering your nighttime habits. Changes to make to your sleep routine can include:

  • not drinking heavy amounts of alcohol, especially at night
  • eliminating caffeine consumption in the evening or even late afternoon depending on your caffeine sensitivity
  • not using your computer, phone, or any electronic device for several hours before bed
  • wearing blue light glasses or adding a blue light filter to your computer screen
  • lowering the temperature in your bedroom
  • meditating or reading right before bed
  • sleeping in total darkness

If changes to sleep habits don’t help, talk with a doctor about medications that may help.

Research published in 2021 indicates that medications that correct an orexin imbalance in people with insomnia may have benefits for managing this condition. These medications are referred to as dual orexin receptor antagonists (DORAs). They’re Food and Drug Administration (FDA) approved and available by prescription.

There are two different orexins:

  • orexin A (hypocretin A)
  • orexin B (hypocretin B)

In the brain, orexins interact with receptors that receive and respond to their chemical signals: orexin receptor type 1 and orexin receptor type 2. DORAs work by blocking one or both receptors from receiving these signals. This reduces the impact of orexin on the sleep-wake cycle.

Studies are ongoing about orexin and its role for reducing insomnia.

You can also consider talking with a cognitive behavioral therapist for help with relaxation training. Cognitive behavioral therapy (CBT) has been found to have benefits for alleviating insomnia.

Narcolepsy treatments

If you think you have narcolepsy, a doctor or sleep therapist can help. They can help determine a diagnosis through tests for narcolepsy and for other potential causes. They’ll ask you about your symptoms and any family history of this condition.

Tests for narcolepsy include:

  • Nocturnal polysomnogram. This test records your brain waves as well as nerve and muscle function during sleep.
  • Multiple sleep latency test. This test measures the severity of your daytime sleepiness and rapidity of REM sleep.

Treatments for narcolepsy center on getting rid of or reducing symptoms. Treatment approaches include behavioral changes and using prescription medications.

Insomnia is a common sleep disorder that affects a large percentage of the population. It’s characterized by the inability to go to sleep or stay asleep. Narcolepsy, on the other hand, is a rare, chronic neurological sleep disorder that’s characterized by severe bouts of daytime drowsiness.

Narcolepsy and insomnia have some symptoms that overlap, but they’re significantly different in the way they present. They also have different causes and treatment options.

If you’re having trouble falling asleep or staying asleep at night, or find yourself having bouts of sleepiness during the day, even after a good night’s rest, contact a doctor to determine whether there’s an underlying cause and treatment options that work well for you.