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

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

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

When medications are used by the criminal justice system, the strong preference of corrections personnel is for naltrexone.

From Slate • May 8, 2018