Narcolepsy symptoms: A look at symptoms and causes of narcolepsy

Awareness of the causes and symptoms of narcolepsy is essential to understanding this rare but risky sleep disorder. We’ll walk you through the common narcolepsy symptoms and causes, and explore how they’re connected.

Narcolepsy causes

Unfortunately, the exact cause of narcolepsy isn’t known.1 Genetics are probably involved, according to the Mayo Clinic.2 The National Center for Biotechnology Information (NCBI) agrees, stating in its A.D.A.M. Medical Encyclopedia that narcolepsy, “can run in families,” and that certain genes are thought to be linked to narcolepsy (but not conclusively).1

Cataplexy is a health condition commonly associated with narcolepsy, though it’s not exactly a narcolepsy cause. In fact, it’s just as often referred to as a symptom of narcolepsy. According to the National Institute of Neurological Disorders and Stroke (NINDS), cataplexy is a sudden period of muscle loss that can cause a person’s body (or parts of it) to suddenly go limp or lose the ability to move while awake. Research shows that cataplexy is found in about 70 percent of people who have narcolepsy.3

Attacks of cataplexy “may be triggered by sudden emotional reactions such as laughter, anger, or fear and may last from a few seconds to several minutes,” according to the narcolepsy fact sheet offered by the U.S. Department of Health and Human Services.4

Narcolepsy symptoms

Narcolepsy symptoms are better known and easier to define than the causes. The symptoms of narcolepsy usually begin at adolescence or early adulthood, according to the National Heart, Lung, and Blood Institute (NHLBI).5 In addition to cataplexy, they often include the following:

Sleep attacks. Defined as “periods of extreme daytime sleepiness and sudden, irresistible bouts of sleep that can strike at any time,” by the NINDS, these common narcolepsy symptoms can last a few seconds to several minutes.3

Sleep paralysis. This symptom of narcolepsy is described as the temporary inability to move or speak while falling asleep or waking. Episodes are temporary and usually last no more than a few minutes, but can be disorienting and cause significant emotional distress.5

Sleep hallucinations. Often found to accompany sleep paralysis, sleep hallucinations (or “hypnagogic hallucinations,” as they’re also known) are images seen just before falling asleep, or while fully awake. These images are “unusually vivid, seem real, and can be frightening,” according to the NINDS.3

Difficulty sleeping at night. Many people with narcolepsy sleep poorly at night. “They may have trouble falling and staying asleep,” states the NHLBI. “Vivid, scary dreams may disturb sleep.”6

Excessive daytime sleepiness (EDS). Calling it the narcolepsy symptom that’s “most consistently experienced by almost all individuals with narcolepsy,” the NINDS describes EDS as an ongoing feeling of mental cloudiness, depressed mood, lack of energy and general, consistent exhaustion.3

Excessive daytime sleepiness is commonly associated with other medical conditions – the NINDS lists some of these, including mood disorders like depression, various viral or bacterial infection, rheumatoid arthritis and congestive heart failure.3 EDS is also a symptom of sleep apnea.7

Of course, drowsiness and bouts of sleepiness aren’t uncommon for the average working American. For that reason, the NHLBI recommends keeping a sleep diary if you find yourself experiencing these narcolepsy symptoms: “Keep a daily record of how easy it is to fall and stay asleep, how much sleep you get at night, and how alert you feel during the day.”8

This blog post contains general information about medical conditions and potential treatments. It is not medical advice. If you have any medical questions, please consult your doctor.

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