Type 1 narcolepsy can cause excessive daytime sleepiness, sudden muscle weakness, and other symptoms, while type 2 narcolepsy is typically less severe.


Narcolepsy is a neurological sleep disorder. It causes daytime sleepiness and other symptoms that may affect your daily activities.

Read on to learn more about the types of narcolepsy, including the symptoms and treatment options.

There are two main types of narcolepsy: type 1 and type 2.

All types of narcolepsy cause excessive daytime sleepiness (EDS). This is the first symptom you’re likely to notice if you develop narcolepsy.

Episodes of EDS are sometimes called sleep attacks. You may feel awake and alert one moment and on the verge of sleeping the next. Each sleep attack may last for a few seconds or as long as several minutes.

What is type 1 narcolepsy?

Type 1 narcolepsy used to be known as “narcolepsy with cataplexy.”

Cataplexy is sudden muscle weakness that is triggered by emotions.

People without narcolepsy typically enter rapid eye movement (REM) sleep after 60–90 minutes of sleep. But if you have narcolepsy, you may enter REM sleep within 15 minutes of falling asleep.

With type 1 narcolepsy, you may also have a low level of hypocretin, a brain hormone that regulates your sleep-wake cycles.

Additionally, in type 1 narcolepsy, you may experience the vivid dream activity and muscle weakness that typically occur with REM sleep while you’re awake, and you may not experience these things while asleep.

What is type 2 narcolepsy?

Type 2 used to be called “narcolepsy without cataplexy.” If you have type 2 narcolepsy, you may have symptoms of narcolepsy without cataplexy, and you may have a normal hypocretin level. The symptoms of type 2 narcolepsy are typically less severe than those of type 1.

What is secondary narcolepsy?

In very rare cases, it’s possible to develop a condition known as secondary narcolepsy. It results from a brain injury, specifically to the hypothalamus region, which regulates sleep cycles.

Type 1 narcolepsy is typically more severe than type 2.

Symptoms of type 1 narcolepsy

With type 1 narcolepsy, you may experience symptoms such as:

Cataplexy is one of the key characteristics of type 1 narcolepsy. This symptom doesn’t usually occur in type 2 narcolepsy.

Cataplexy

Cataplexy is a sudden loss of muscle tone that occurs during waking hours. It can last for seconds to minutes and may affect your whole body or a localized area, such as your head and neck.

The muscle weakness is similar to the muscle weakness that occurs during REM sleep at night. It can cause muscle limpness, which might make you feel like you’re going to collapse. It can also cause involuntary muscle movements, but this is rare.

If you have type 1 narcolepsy, you’re most at risk for cataplexy after experiencing a strong emotional response such as:

  • excitement
  • stress
  • fear
  • laughter

Cataplexy may not be the first symptom of type 1 narcolepsy that you experience. It usually develops after the onset of EDS.

Some people experience cataplexy a few times throughout their lives, while others have several episodes per week. The effects may last for up to a few minutes each time.

Diagnosis

To diagnose narcolepsy, doctors in a sleep disorders clinic may conduct sleep tests that measure your brain activity while you’re sleeping and how quickly you fall asleep.

In some cases, a doctor may recommend a spinal tap to determine your hypocretin level.

Doctors will diagnose narcolepsy if you have symptoms that have occurred at least three times per week over the past 3 months, along with one of the following:

  • a low hypocretin level
  • cataplexy that occurs at least several times per month
  • onset of REM sleep after less than 15 minutes of sleep, or two or more REM periods in one night that begin after less than 8 minutes of sleep, on average, during a formal sleep test

In general, the symptoms of type 2 narcolepsy tend to be less severe than those of type 1 narcolepsy.

Symptoms

Type 2 narcolepsy may cause:

  • EDS
  • sleep paralysis
  • hallucinations
  • insomnia

Type 2 narcolepsy doesn’t usually cause cataplexy.

Diagnosis

Doctors test for type 2 narcolepsy the same way they test for type 1 narcolepsy.

People with type 2 narcolepsy have normal levels of hypocretin.

There’s no cure for narcolepsy, but treatments are available to help manage the symptoms. Your treatment may depend on the symptoms you experience.

To treat EDS, a doctor may prescribe a central nervous system stimulant such as:

If that doesn’t work, they may prescribe:

To treat cataplexy, a doctor may prescribe one of the following:

  • a selective serotonin reuptake inhibitor such as fluoxetine (Prozac, Sarafem)
  • a serotonin-norepinephrine reuptake inhibitor such as venlafaxine (Effexor XR)
  • a tricyclic antidepressant such as clomipramine (Anafranil), imipramine (Tofranil), or protriptyline (Vivactil)
  • a central nervous system depressant, such as sodium oxybate (Xyrem)

Lifestyle strategies

A doctor may encourage you to practice certain lifestyle habits, such as maintaining a regular sleep schedule and taking short, scheduled naps.

Some people may rely on a narcolepsy service dog trained to alert them that an episode is coming.

Additionally, some people with narcolepsy may meet disability criteria and be able to receive Social Security disability benefits.

If you experience extreme sleepiness during waking hours or other potential symptoms of narcolepsy, let a doctor know.

To diagnose narcolepsy, a doctor will ask about your symptoms and order sleep tests. They may also collect a sample of your cerebrospinal fluid to check your hypocretin level.

Let the doctor know if your symptoms change over time. Their treatment recommendations will depend on your symptoms and the type of narcolepsy you have.