cat·​a·​plexy | \ ˈka-tə-ˌplek-sē How to pronounce cataplexy (audio) \
plural cataplexies\ ˈka-​tə-​ˌplek-​sēz How to pronounce cataplexy (audio) \

Definition of cataplexy

: sudden loss of muscle power following a strong emotional stimulus

Examples of cataplexy in a Sentence

Recent Examples on the Web Symptoms such as hallucinations, sleep paralysis, and cataplexy may follow, says Manjamalai Sivaraman, MD, FAASM, a sleep medicine specialist and neurologist at the University of Missouri. Sarah Fielding,, 8 Dec. 2021 Excessive daytime sleepiness and cataplexy can improve after several weeks of regularly taking sodium oxybate. Sarah Fielding,, 6 Dec. 2021 People with narcolepsy type 2 may experience all the symptoms of narcolepsy except cataplexy—and their symptoms are often less severe, says the National Institute of Neurological Disorders and Stroke (NINDS). Sarah Fielding,, 8 Dec. 2021 In both cases, more exercise inversely correlated with the degree of sleepiness and frequency of cataplexy episodes experienced. Sarah Fielding,, 6 Dec. 2021 While some people may have multiple episodes a day, others may only experience cataplexy once or twice a year. Sarah Fielding,, 3 Dec. 2021 The breakthrough designation for AXS-12 being revoked was for cataplexy as a condition in narcolepsy. Trefis Team, Forbes, 18 Oct. 2021 The breakthrough designation for AXS-12 being revoked was for cataplexy as a condition in narcolepsy. Trefis Team, Forbes, 18 Oct. 2021 Narcolepsy type 2, in which a person experiences general narcolepsy symptoms but does not have cataplexy. Sarah Fielding,, 3 Nov. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cataplexy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of cataplexy

1883, in the meaning defined above

History and Etymology for cataplexy

German Kataplexie, from Greek kataplēxis, from kataplēssein to strike down, terrify, from kata- + plēssein to strike — more at plaint

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The first known use of cataplexy was in 1883

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Cite this Entry

“Cataplexy.” Dictionary, Merriam-Webster, Accessed 10 Aug. 2022.

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More Definitions for cataplexy


cat·​a·​plexy | \ ˈkat-ə-ˌplek-sē How to pronounce cataplexy (audio) \
plural cataplexies\ -​sēz How to pronounce cataplexy (audio) \

Medical Definition of cataplexy

: a sudden loss of muscle control with retention of clear consciousness that follows a strong emotional stimulus (as elation, surprise, or anger) and is a characteristic symptom of narcolepsy

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