Definitions for naltrexonenælˈtrɛk soʊn
Random House Webster's College Dictionary
a nonaddictive substance, C20H23NO4, used in the treatment of heroin addiction and opiate overdose.
Origin of naltrexone:
1970–75; by rearrangement of parts of its chemical name
an oral antagonist against the action of opiates
An opiate antagonist used to treat opioid dependence
U.S. National Library of Medicine
Derivative of noroxymorphone that is the N-cyclopropylmethyl congener of NALOXONE. It is a narcotic antagonist that is effective orally, longer lasting and more potent than naloxone, and has been proposed for the treatment of heroin addiction. The FDA has approved naltrexone for the treatment of alcohol dependence.