naltrexone

noun

nal·​trex·​one nal-ˈtrek-ˌsōn 

: a synthetic opiate antagonist C₂₀H₂₃NO₄ administered in the form of its hydrochloride

Examples of naltrexone in a Sentence

Recent Examples on the Web

The drug is one of several medications, along with methadone and naltrexone, used for this purpose. — Encyclopedia Britannica, 28 Aug. 2026

During the years that the journal spent considering how to respond to the university’s request for a retraction, more doctors across the country began prescribing naltrexone. — Amy Yurkanin, ProPublica, 24 Aug. 2026

Medications like naltrexone can reduce heavy drinking and cravings, and research shows that starting treatment in the emergency department can improve quality of life. — Jonathan Hunt-Glassman, Fortune, 2 Apr. 2026

Some medications, like naltrexone and buprenorphine, are used specifically to prevent relapse in people trying to recover from opioid use disorder. — Jon Hamilton, NPR, 10 Mar. 2026

Word History

Etymology

N-allyl + trex- (as in methotrexate) + -one

First Known Use

1973, in the meaning defined above

Medical Definition

naltrexone

noun

nal·​trex·​one nal-ˈtrek-ˌsōn 

: a synthetic opiate antagonist administered especially in the form of its hydrochloride C₂₀H₂₃NO₄·HCl to maintain a drug-free state in detoxified opiate-dependent patients or to maintain abstinence in alcohol-dependent patients