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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

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

Consequently, large, well-controlled clinical trials of low-dose naltrexone are scarce.

From Seattle Times Jan. 12, 2022

The researchers gave depressed patients naltrexone to block the opioid receptor before administering ketamine, and found that this eliminated ketamine’s antidepressant effects but not its hallucinatory side effects.

From Scientific American Feb. 22, 2019

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