pyrimethamine

noun

py·​ri·​meth·​amine ˌpī-rə-ˈme-thə-ˌmēn How to pronounce pyrimethamine (audio)
: a folic acid antagonist C12H13ClN4 used in the chemoprophylaxis or treatment of malaria and in the treatment of toxoplasmosis

Word History

Etymology

pyrimidine + ethyl + amine

First Known Use

1952, in the meaning defined above

Time Traveler
The first known use of pyrimethamine was in 1952

Rhymes for pyrimethamine

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Browse Nearby Words

pyriform
pyrimethamine
pyrimidine
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Cite this Entry

“Pyrimethamine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pyrimethamine. Accessed 20 Apr. 2025.

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Medical Definition

pyrimethamine

noun
py·​ri·​meth·​amine ˌpī-rə-ˈmeth-ə-ˌmēn How to pronounce pyrimethamine (audio)
: a folic acid antagonist C12H13ClN4 that is used in the treatment of toxoplasmosis and in the prevention and treatment of malaria

Note: Pyrimethamine is marketed under the trademark Daraprim.

More from Merriam-Webster on pyrimethamine

Britannica.com: Encyclopedia article about pyrimethamine

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