mifepristone

American  

[mif-uh-pris-tohn] / ˌmɪf əˈprɪs toʊn /

noun

1. an antigestational drug, C 29 H 35 NO 2 , that prevents a fertilized egg from attaching to the uterine wall by blocking the action of progesterone.

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mifepristone British  

/ mɪˈfɛprɪˌstəʊn /

noun

1. an antiprogestogenic steroid, used in the medical termination of pregnancy. Formula: C 29 H 35 NO 2

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Etymology

Origin of mifepristone

1985–90; probably alteration of (a)mi(no)phe(nol) + pr(opyl) + est(radiol) + -one

Example Sentences

He reasoned that the FDA didn’t have adequate data about adverse events or the safety of telehealth when writing the current rules on mifepristone.

From Slate • Apr. 13, 2026

Corcept has one marketed product, called Korlym, which is a presentation of the drug mifepristone used to control hyperglycemia in certain patients with Cushing syndrome.

From Barron's • Dec. 31, 2025

The FDA also approved a generic version of mifepristone in 2019.

From The Wall Street Journal • Oct. 2, 2025

Under federal law, the requirements must address a specific risk posed by a drug and cannot be “unduly burdensome” on patients, and the new application to mifepristone “fails to meet that standard,” Bonta said.

From Los Angeles Times • Jun. 5, 2025

Any decision to shrink agencies like the FDA would have to go through Congress, and changes in mifepristone regulations could also face legal challenges.

From Salon • Nov. 8, 2024