Conditions & Treatments


Narcolepsy is a chronic, neurological sleep disorder with no known cause. It involves the body's central nervous system. Narcolepsy is a genetic disorder, but what causes narcolepsy is not yet known.


What is narcolepsy?

Narcolepsy is a chronic, neurological sleep disorder with no known cause. It involves the body's central nervous system. Narcolepsy is a genetic disorder, and is caused by a deficiency in the production of a neuropeptide (known as hypocretin or orexin) by a part of the brain called the hypothalamus.

The main characteristic of narcolepsy is excessive and overwhelming daytime sleepiness, even after adequate nighttime sleep. A person with narcolepsy is likely to become drowsy or to fall asleep at inappropriate times and places, and sleep attacks may occur with or without warning.

Attacks can occur repeatedly in a single day, drowsiness may persist for prolonged periods of time, and nighttime sleep may be fragmented with frequent awakenings.

What are the symptoms of narcolepsy?

The following are the most common symptoms of narcolepsy. However, individuals may experience symptoms differently. Symptoms may include:

  • Excessive daytime sleepiness (EDS). An overwhelming desire to sleep at inappropriate times.

  • Cataplexy. A sudden loss of muscle control ranging from slight weakness to total collapse.

  • Sleep paralysis. Being unable to talk or move for about 1 minute when falling asleep or waking up.

  • Hypnagogic and hypnopompic hallucinations. Vivid and often scary dreams and sounds reported when falling asleep (hypnagogic) or on awakening (hypnopompic). 

Secondary or auxiliary symptoms include:

  • Automatic behavior. Performing routine tasks without conscious awareness of doing so, and often without memory of it.

  • Disrupted nighttime sleep, including multiple arousals

  • Dream-enacting behaviors, in which patients may act out their dreams 

  • Other difficulties may result from one's continuing struggle to cope, including:

    • Feelings of intense fatigue and continual lack of energy

    • Depression

    • Difficulty in concentrating and memorizing

    • Vision (focusing) problems

    • Eating binges

    • Weak limbs

    • Difficulties in handling alcohol

How is narcolepsy diagnosed?

A combination of EDS and cataplexy provide for a preliminary clinical diagnosis.

In addition to a complete medical history and physical examination, laboratory tests to confirm diagnosis and plan treatment may include:

  • Overnight polysomnogram (PSG). A sleep test to monitor various parameters during an entire night of sleep. This is to evaluate for other possible contributing sleep-related disorders. 

  • Multiple Sleep Latency Test (MSLT). Measures sleep onset and how quickly rapid eye movement (REM) sleep occurs during 5 naps. A mean sleep latency on the 5 naps of 8 minutes or less, in conjunction with 2 or more sleep-onset REM periods, is considered diagnostic of narcolepsy. 

  • Cerebral Spinal Fluid (CSF) hypocretin levels. A spinal tap for CSF to evaluate for possible hypocretin deficiency is used when there is concern about the possible diagnosis and other testing is either not possible or negative. 

Genetic testing is no longer used because the human leukocyte antigen (HLA) markers may be negative in patients with narcolepsy and/or may be positive in patients who do not have narcolepsy. However, a link between reduced HLA markers and T cells, which are vital in the body's immune system, continued to be studied. 

How is narcolepsy treated?

Specific treatment will be determined by your health care provider based on:

  • Your age, overall health, and medical history

  • Severity of the disease

  • Your tolerance for specific medications, procedures, or therapies

  • Expectations for the course of the disease

  • Your opinion or preference

The goal of treatment of narcolepsy is for the patient to remain as alert as possible during the day and to minimize any recurring episodes of cataplexy, while using a minimal amount of medication.

  • Medications. Excessive daytime sleepiness and cataplexy are treated separately, with central nervous system stimulants usually prescribed for EDS and antidepressants for cataplexy.

  • Nap therapy. Two or 3 short naps during the day may help control sleepiness and maintain alertness. Most patients with narcolepsy typically feel more alert and refreshed after awakening. 

  • Proper diet

  • Regular exercise

  • Behavioral therapy

Treatment Programs

Massachusetts General Hospital understands that a variety of factors influence patients' health care decisions. That's just one reason why we're dedicated to ensuring patients understand their diagnosis and treatment options. Because a single option might not serve all patients, we offer a wide range of coordinated treatments and related services across the hospital. Patients should consult with their primary care doctor or other qualified health care provider for medical advice and diagnosis information.

Select a treatment program for more information:


  • Neuroendovascular Program
    Working as part of the Fireman Vascular Center, the interventional specialists of the Neuroendovascular Program perform minimally invasive, image-guided treatments for conditions including stroke and cerebral aneurysm. In addition, our specialty-trained radiologists use the latest imaging technologies to provide diagnostic exams for a full range of neurological conditions.
MassGeneral Hospital for Children

  • Pediatric Sleep Disorders Program
    Sleep problems, including problems falling asleep, staying asleep, disrupted sleep and excessive daytime sleepiness are common in children. The Sleep Disorders Program at MassGeneral Hospital for Children provides comprehensive evaluation and treatment for children with disorders of sleep.
Department of Neurology

  • General Pediatric Neurology
    General Pediatric Neurology physicians diagnose and treat all neurological disorders in children, infants and adolescents.
Obstetrics and Gynecology

  • Midlife Women's Health Center
    The Massachusetts General Hospital Midlife Women’s Health Center brings together experts from more than 15 specialties to improve, promote and advance health care for women at menopause and beyond through research, collaboration and education.
Pulmonary and Critical Care Medicine

  • Spaulding Sleep Center
    The Spaulding Sleep Center uses the latest technology to diagnose and treat sleep disorders, with a focus on patients with cardiac and/or pulmonary disease.

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