Sleep Disorders Narcolepsy Symptoms

Narcolepsy symptoms include excessive daytime sleepiness, sleep paralysis, hallucinations and cataplexy. All cases of narcolepsy present with daytime sleepiness. Other symptoms vary depending on the individual, with few people displaying all four major narcolepsy symptoms.

Excessive Daytime Sleepiness

Daytime sleepiness describes both all-day drowsiness and sudden “sleep attacks.” A person with narcolepsy may experience several sleep attacks a day, falling asleep at unexpected or inappropriate times.

In most cases sleep attacks occur when the individual engages in passive activities such as sitting, reading or watching television. Less commonly, sleep attacks also occur when working, eating, driving or having sex.

A sleep attack typically lasts from 15 to 60 minutes. How often daytime sleepiness causes sleep attacks depends on the individual. Daytime sleepiness caused by narcolepsy does not always result in sleep attacks. While some people experience several sleep attacks a day others remain awake but suffer from extreme drowsiness.

Cataplexy Symptoms

Cataplexy is the second most common narcolepsy symptom. Cataplexy describes a sudden loss of muscle tone. Cataplexy symptoms can affect the entire body or only parts of the body. Mild cataplexy symptoms may present as a feeling of weakness or an inability to keep the head upright. Severe cataplexy symptoms can result in complete physical collapse.

A cataplexy attack can last several minutes. Cataplexy symptoms can be triggered by intense emotions. Laughter and excitement are common cataplexy triggers, but anger, fear or shock can also produce cataplexy.

Cataplexy symptoms without the presence of narcolepsy are rare. Indeed, the presence of daytime sleepiness and cataplexy together are enough to make a narcolepsy diagnosis. Cataplexy symptoms appear to occur when the brain mistakenly signals the temporary paralysis that accompanies rapid eye movement (REM) sleep.

Sleep Paralysis

Sleep paralysis is one of the less common narcolepsy symptoms, and also one of the most frightening. People experiencing sleep paralysis cannot move or speak for a period of time when they wake up. Sleep paralysis usually only lasts for a few minutes.

Like cataplexy, sleep paralysis appears to be caused when the paralysis seen during REM sleep occurs at inappropriate times

Hypnagogic Hallucinations

Narcolepsy symptoms may include intense hallucinations when falling asleep or waking up. Hallucinations experienced when falling asleep are called hypnagogic hallucinations. Hallucinations experienced when waking up are hypnopompic hallucinations.

Hypnagogic hallucinations include auditory, visual and tactile hallucinations. Hypnagogic hallucinations are often frightening, especially as the individual believes he is awake.

Like sleep paralysis, hypnagogic hallucinations can occur without narcolepsy. Hypnagogic hallucinations do, however, often affect people with narcolepsy.

Other Narcolepsy Symptoms

Daytime sleepiness, cataplexy symptoms, hypnagogic hallucinations and sleep paralysis are the most common narcolepsy symptoms, but by no means the only ones. Other narcolepsy symptoms include insomnia and restless leg syndrome.

People with narcolepsy may also have difficulty concentrating, learning and retaining information due to daytime sleepiness. Work and personal relationships may also suffer. Seek professional help if you have narcolepsy syndromes.


Health Communities. (2000). Signs and symptoms of narcolepsy. Retrieved August 23, 2010, from

Mayo Clinic staff. (2010). Narcolepsy. Retrieved August 23, 2010, from

National Heart Lung and Blood Institute. (2008). Narcolepsy. Retrieved August 23, 2010, from

Stanford School of Medicine. (n.d.). About narcolepsy. Retrieved August 23, 2010, from