Narcolepsy is a type of neurological sleep disorder. It causes daytime sleepiness and other symptoms that may affect your routine activities.
Read on to learn more about the different types of narcolepsy, including the symptoms and treatment options.
There are two main types of narcolepsy: type 1 and type 2.
Type 1 narcolepsy used to be known as “narcolepsy with cataplexy.” Type 2 used to be called “narcolepsy withoutcataplexy.”
In very rare cases, a person may develop another type of narcolepsy known as secondary narcolepsy. It results from a brain injury, specifically to the hypothalamus region, which regulates your sleep cycles.
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 described as “sleep attacks.” You may feel awake and alert one moment, then on the verge of sleeping the next. Each sleep attack may last for a few seconds or as long as several minutes.
Experts estimate 10 to 25 percent of people with narcolepsy experience other symptoms, too.
In addition to EDS, type 1 narcolepsy may cause other symptoms:
- Cataplexy is sudden muscle weakness that occurs when you’re awake.
- Sleep paralysis is a temporary inability to speak or move that may occur when you’re falling asleep or waking up.
- Hallucinations are vivid images or other sensory experiences that may occur when you’re falling asleep or waking up.
- Insomnia is difficulty falling or staying asleep at night.
The presence of cataplexy is one of the key characteristics of type 1 narcolepsy. This symptom doesn’t usually occur in type 2 narcolepsy.
In general, the symptoms of type 2 narcolepsy tend to be less severe than those of type 1 narcolepsy.
In addition to EDS, type 2 narcolepsy may cause:
- sleep paralysis
Type 2 narcolepsy doesn’t usually cause cataplexy.
Cataplexy refers to a loss of muscle tone that occurs suddenly during waking hours.
The muscle weakness is similar to the muscle weakness that occurs during rapid eye movement (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.
Cataplexy affects people with type 1 narcolepsy. It’s not common with type 2.
If you have type 1 narcolepsy, you’re most at risk for cataplexy after experiencing a strong emotional response, such as excitement, stress, or fear.
Cataplexy may not be the first symptom of type 1 narcolepsy you experience. Instead, 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.
There’s no current cure for narcolepsy, but treatments are available to help manage symptoms.
To treat EDS, your doctor may prescribe a central nervous system stimulant, such as modafinil (Provigil) or armodafinil (Nuvigil).
If that doesn’t work, they may prescribe an amphetamine-like stimulant, such as methylphenidate (Aptensio XR, Concerta, Ritalin).
To treat cataplexy, your doctor may prescribe one of the following:
- a selective serotonin reuptake inhibitor (SSRI) or serotonin-norepinephrine reuptake inhibitor (SNRI), such as fluoxetine (Prozac, Sarafem) or venlafaxine (Effexor XR)
- a tricyclic antidepressant, such as clomipramine (Anafranil), imipramine (Tofranil), or protriptyline (Vivactil)
- a central nervous system depressant, known as sodium oxybate (Xyrem)
Your doctor may also encourage you to practice certain lifestyle habits, such as maintaining a regular sleep schedule and taking short scheduled naps.
If you experience extreme sleepiness during waking hours or other potential symptoms of narcolepsy, let your doctor know.
To diagnose narcolepsy, your doctor will ask you about your symptoms and order sleep tests. They may also collect a sample of your cerebral spinal fluid to check your hypocretin levels. This brain protein regulates your sleep-wake cycles.
Let your doctor know if your symptoms change over time. Their recommended treatment plan will depend on your symptoms and type of narcolepsy you have.