Science Stories

“A few summers ago I was at the pool and my little neighbor; he was just playing in the pool and giggling, so I was giggling. Then suddenly I was sinking; I couldn’t get my legs to move.” – Claire, person living with narcolepsy

About 1 in 2,000 people in the U.S. are estimated to have narcolepsy , and more than half of people living with narcolepsy experience cataplexy.2

What is Cataplexy?

Understanding a Leading Symptom of Narcolepsy

Narcolepsy is an often misunderstood and under-recognized condition. Cataplexy is a major symptom of narcolepsy, a chronic neurological condition that involves other symptoms such as excessive daytime sleepiness – that can result in difficulty focusing and maintaining alertness, along with sleep paralysis and vivid hallucinations when falling asleep or waking up.2 A person cannot have cataplexy without having narcolepsy except in extremely rare cases.3

Cataplexy is sudden episodes of muscle paralysis often triggered by emotions like humor, surprise, or anger.2 The presentation of cataplexy episodes varies from facial drooping, jaw weakening, slight knee buckling or neck weakness to falling to the ground for up to several minutes.2 Given people can experience a range of triggering emotions throughout daily life, a cataplexy episode can occur at any time – it could be when a person is playing with their children, cooking or driving.2 The location does not matter, cataplexy can unexpectedly occur – it might also not be as visible or noticeable as one might expect.2,3

About 1 in 2,000 people in the U.S. are estimated to have narcolepsy1, and more than half of people living with narcolepsy experience cataplexy2. During a cataplexy episode, the person remains conscious and aware of their surroundings, even if unable to speak or move.2 The results of a cataplexy episode can also cause physical injury, for example fracturing wrists or other body parts during a fall.2

Claire, a person living with narcolepsy, describes a time when cataplexy put her life at risk. “A few summers ago, I was at the pool and my little neighbor, he was just playing in the pool and giggling, so I was giggling. Then suddenly I was sinking; I couldn’t get my legs to move.”

Almost all people who experience cataplexy have extremely low levels of the naturally occurring chemical hypocretin, which promotes wakefulness and stabilizes sleep/wake transition.1,2

In people with cataplexy, the loss of hypocretin is believed to be irreversible and lifelong. However, cataplexy can be managed in most individuals with certain medications.3

Claire’s experience is just one example of the impact cataplexy can have on a person’s daily life. People with cataplexy may learn to avoid situations or emotions that trigger a cataplexy episode—meaning they may resist laughing, for example, to avoid prompting an episode.2

1Narcolepsynetwork.org. (2019). Narcolepsy Fast Facts. [online] Available at: https://narcolepsynetwork.org/about-narcolepsy/narcolepsy-fast-facts/ [Accessed September 6, 2019].
2Ahmed I, Thorpy, M. Clinical Features, Diagnosis and Treatment of Narcolepsy. Clin Chest Med. 2010;31(2):371-381.
3Ninds.nih.gov. (2019). Narcolepsy Fact Sheet. [online] Available at: https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Narcolepsy-Fact-Sheet [Accessed September 6, 2019].