hep·​a·​rin | \ ˈhe-pə-rən How to pronounce heparin (audio) \

Definition of heparin

: a mucopolysaccharide sulfuric acid ester that is found especially in the liver and lungs, that prolongs the clotting time of blood, and that is used medically in the form of its sodium salt

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Other Words from heparin

heparinized \ ˈhe-​pə-​rə-​ˌnīzd How to pronounce heparinized (audio) \ adjective

Did You Know?

Heparin is an organic compound used to prevent blood from clotting in the heart or blood vessels during and after surgery, and for initial treatment of various heart, lung, or circulatory disorders in which there is an increased risk of blood clotting. A mixture of complex carbohydrate molecules, heparin occurs naturally in liver and lung tissues. It was discovered in 1922 and originally used to prevent clotting in blood taken for laboratory tests.

Examples of heparin in a Sentence

Recent Examples on the Web His team has started such a study and going forward will test varying doses of either the classic blood thinner heparin or one of the newer, oral anticoagulant drugs such as dabigatran, a direct thrombin inhibitor. Maggie Fox, CNN, "Blood thinners may help patients with severe Covid-19 infections, study finds," 6 May 2020 Some doctors have tried using blood thinners such as heparin to try to reduce the clotting, but there's not enough evidence to show whether such treatment helps patients survive. Maggie Fox, CNN, "New Covid-19 crisis hits ICUs as more patients need dialysis," 17 Apr. 2020 The contaminant, which is very cheap, was similar in chemical structure to heparin and was able to go undetected in routine tests. Marsha Blackburn, STAT, "The coronavirus outbreak exposes the U.S.’s pharma supply chain vulnerability," 14 Feb. 2020 The company has since shipped several other essential medicines, including the blood thinner heparin and the opioid overdose rescue drug, naloxone. Beth Mole, Ars Technica, "California considers selling its own generic prescription drugs," 10 Jan. 2020 The wipeout could create shortages of food and supplies of products made from pigs, such as the blood-thinner heparin. National Geographic, "Where do your backyard birds migrate in the winter?," 7 Nov. 2019 The blood-thinner heparin, made from pig products and largely sourced from China, could also face shortages, Schipp said. Ryan W. Miller, USA TODAY, "Quarter of all pigs worldwide could die from swine fever, animal health organization says," 31 Oct. 2019 To continue reading this story, TRY IT NOW Born: July 13, 1950 Jan. 9, 1982: 4-week-old Rolando Santos is injected with the blood thinner heparin at Medical Center Hospital. Sept. 17, 1982: 15-month-old Chelsea Ann McClellan dies. San Antonio Express-News, "Timeline: Genene Jones' path from murder to parole," 18 Apr. 2018 Its version of the blood-thinner heparin drew plaudits — and a bump in stock prices — after a contamination outbreak in other thinners killed dozens of people. John Wilkens, Pomerado News, "Physician turned entrepreneur begins work with new patients: Union-Tribune and L.A. Times," 13 Apr. 2018

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

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First Known Use of heparin

1918, in the meaning defined above

History and Etymology for heparin

International Scientific Vocabulary, from Greek hēpar liver

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Time Traveler for heparin

Time Traveler

The first known use of heparin was in 1918

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Statistics for heparin

Last Updated

17 May 2020

Cite this Entry

“Heparin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heparin. Accessed 4 Jun. 2020.

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More Definitions for heparin


hep·​a·​rin | \ ˈhep-ə-rən How to pronounce heparin (audio) \

Medical Definition of heparin

: a glycosaminoglycan sulfuric acid ester that occurs especially in the liver and lungs, that prolongs the clotting time of blood by preventing the formation of fibrin, and that is administered parenterally in the form of its sodium salt in vascular surgery and in the treatment of postoperative thrombosis and embolism — see liquaemin — compare antiprothrombin, antithrombin

More from Merriam-Webster on heparin

Britannica.com: Encyclopedia article about heparin

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