methylene blue


Definition of methylene blue

: a basic thiazine dye C16H18ClN3S·3H2O used especially as a biological stain, an antidote in cyanide poisoning, and an oxidation-reduction indicator

Examples of methylene blue in a Sentence

Recent Examples on the Web Currently, only three dyes with fluorescent properties used as optical imaging contrast agents—methylene blue, indocyanine green and fluorescein—are approved for human use by the U.S. Food and Drug Administration (FDA). Courtney Sexton, Smithsonian Magazine, 18 Sep. 2020 Warren’s patient recovered after two doses of methylene blue and an overnight stay at the hospital. Wire Service, The Mercury News, 19 Sep. 2019 The first-line treatment for the condition is a drug called methylene blue, which can spur the enzymatic reduction of the iron back to its normal state. Beth Mole, Ars Technica, 23 Sep. 2019 The woman in this case made a full recovery after intravenous treatment of methylene blue, her doctors reported in The New England Journal of Medicine. Beth Mole, Ars Technica, 23 Sep. 2019 Methemoglobinemia is easily treatable, using a medication that, perhaps ironically, is called methylene blue. NBC News, 18 Sep. 2019 Dutch, American and Malian scientists working in Ouélessébougou, Mali, found that adding methylene blue to a typical treatment regimen cleared gametocytes from the bloodstream within two days. Donald G. Mcneil Jr., New York Times, 9 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'methylene blue.' 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 methylene blue

1882, in the meaning defined above

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Time Traveler for methylene blue

Time Traveler

The first known use of methylene blue was in 1882

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Dictionary Entries Near methylene blue


methylene blue

methylene chloride

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Cite this Entry

“Methylene blue.” Dictionary, Merriam-Webster, Accessed 17 Jan. 2022.

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More Definitions for methylene blue

methylene blue


Medical Definition of methylene blue

: a basic thiazine dye C16H18ClN3S·3H2O used in the treatment of methemoglobinemia, as an antidote in cyanide poisoning, as a biological stain, and as an oxidation-reduction indicator

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