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naltrexone

American  
[nal-trek-sohn] / nælˈtrɛk soʊn /

noun

Pharmacology.
  1. a nonaddictive substance, C 2 0 H 2 3 NO 4 , used in the treatment of heroin addiction and opiate overdose.


naltrexone British  
/ nælˈtrɛksəʊn /

noun

  1. a narcotic antagonist, similar to morphine, used chiefly in the treatment of heroin addiction

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of naltrexone

First recorded in 1970–75; by rearrangement of parts of its chemical name

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Low-dose naltrexone has been shown to reduce fatigue and lower platelet aggregation.

From Science Daily Jan. 8, 2026

Steroids, low-dose naltrexone, melatonin, lecithin, goldenseal, sceletium and a whole world of anti-inflammatory botanical ferments like kefir.

From Salon Dec. 7, 2023

Cacciatore, whose daughter died in 1994, and who continues to identify as “a bereaved mother,” says the naltrexone study betrays a “gross, contemptuous” attitude toward grieving.

From Seattle Times Nov. 24, 2023

However, naltrexone, in both short- and long-acting forms, has the opposite pharmacology: it antagonizes mu receptors, occupying them without activating them.

From Scientific American Sep. 13, 2023

Among the most popular are low-dose naltrexone, anticoagulants, antivirals, beta blockers, statins, antihistamines to calm overactive mast cells, and probiotics to improve gut health.

From Slate May 8, 2023

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