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.

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naltrexone British  

/ nælˈtrɛksəʊn /

noun

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

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Etymology

Origin of naltrexone

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

Example Sentences

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

From Science Daily • Jan. 8, 2026

I have read about low-dose naltrexone and have discussed it with my primary care provider.

From Seattle Times • Jan. 12, 2022

These elegant studies demonstrate that when opioid receptors are blocked – in one example by a drug called naltrexone – people still experienced euphoria and reduced pain and anxiety after exercise.

From Salon • Jan. 4, 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

In nearly all cases, that treatment was naltrexone.

From Slate • May 8, 2018