nal·trex·one | \ nal-ˈtrek-ˌsōn \

Definition of naltrexone 

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

Examples of naltrexone in a Sentence

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About 6 percent of patients were on the opioid blocker, naltrexone (brand name Vivitrol) but often for just one month. Martha Bebinger, Washington Post, "After Opioid Overdose, Only 30 Percent Get Medicine To Treat Addiction," 19 June 2018 At Gaudenzia, a large regional treatment program, naltrexone is used often with young adults. Rita Giordano,, "Opioid addiction treatment with medicine works best. Why don't more young people get it?," 11 Apr. 2018 After a rocky start, the Trump administration has gotten on board with addiction medications, which also include methadone and naltrexone. Abby Goodnough, New York Times, "When an Iowa Family Doctor Takes On the Opioid Epidemic," 23 June 2018 Vivitrol, or injectable naltrexone, is a newer medication that works well for some people. Felice J. Freyer,, "Five myths about medications to treat addiction," 7 June 2018 Buprenorphine and naltrexone are a different story. Patrick Skerrett, STAT, "Hey, doctors: Why aren’t you stepping up to treat people with opioid addiction?," 5 July 2018 Other options are buprenorphine and injectable naltrexone. Fox News, "Should people with drug addictions be forced into rehab?," 24 June 2018 Buprenorphine withdrawal treatment should be undertaken only if a plan is in place for giving inmates naltrexone or keeping them on buprenorphine. Terry Demio, USA TODAY, "Incarcerated opioid addicts often have to tough out withdrawal. Some jails say they have a better way.," 23 May 2018 Jefferson County Jail in Golden, Colorado, began in April to use naltrexone, a drug that works in the brain to keep opiates from working and helps stop cravings, for its addicted inmates, KUSA-TV, Denver reported. Terry Demio, USA TODAY, "Incarcerated opioid addicts often have to tough out withdrawal. Some jails say they have a better way.," 23 May 2018

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

1973, in the meaning defined above

History and Etymology for naltrexone

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

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5 Sep 2018

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The first known use of naltrexone was in 1973

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nal·trex·one | \ nal-ˈtrek-ˌsōn \

Medical Definition of naltrexone 

: 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

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