nal·​trex·​one | \ nal-ˈtrek-ˌsōn How to pronounce naltrexone (audio) \

Definition of naltrexone

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

Examples of naltrexone in a Sentence

Recent Examples on the Web Naltrexone, the active ingredient in VIVITROL, is the same active ingredient in tablets taken by mouth that contain naltrexone. Ben Busby And Kristen Yelton, Good Housekeeping, "Opioid Dependence Is Part of Our Relationship, But Doesn’t Define It," 29 June 2020 Few have openly embraced the medicines, which can also include methadone or naltrexone (also known as Vivitrol). Chiara Eisner,, "Medical community struggles with own opioid dilemma: How to heal the healers?," 19 Feb. 2020 The program educates medical providers about prescribing medications, such as naltrexone and buprenorphine, that are effective in treating opioid addiction. Lauren Caruba,, "UT Health San Antonio to oversee statewide opioid addiction program," 14 Feb. 2020 Weight loss drugs approved for long-term use include orlistat (brand name Xenical), lorcaserin (Belviq) and liraglutide (Saxenda) as well as the combination drugs naltrexone-bupropion (Contrave) and phentermine-topiramate (Qsymia). Jacqueline Howard, CNN, "Weight loss drug Belviq tied to 'possible increased risk of cancer,' FDA says," 15 Jan. 2020 That approach uses drugs such as methadone, buprenorphine and extended-release naltrexone to wean people with addiction back to a lower and safer opioid dose, or off the painkillers altogether. Melissa Healystaff Writer, Los Angeles Times, "Opioid addiction can be overcome with mindfulness, study suggests," 17 Oct. 2019 And in Warren County, Common Pleas Judge Robert Peeler, who pioneered the use of injectable naltrexone in 2013 for his Drug Court, said participants with opioid addiction there now may be treated with methadone or bupenorphine. Terry Demio,, "'I will die' without it: Hamilton County Jail offers addicted inmates meds behind bars," 19 June 2019 When naltrexone is used to treat addiction in pill form, it's prescribed at 50 milligrams. Alex Smith, Kaiser Health,, "In tiny doses, an addiction medication moonlights as treatment for chronic pain," 7 Oct. 2019 Drugs like buprenorphine, morphine, and naltrexone should be used instead, Pacula said. Carla K. Johnson,, "Medical marijuana laws are no answer for US opioid deaths, study finds," 11 June 2019

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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The first known use of naltrexone was in 1973

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Cite this Entry

“Naltrexone.” Dictionary, Merriam-Webster, Accessed 20 Oct. 2020.

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nal·​trex·​one | \ nal-ˈtrek-ˌsōn How to pronounce naltrexone (audio) \

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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