Studies of EN-1639A (Naltrexone): A New Narcotic Antagonist

Abstract

The narcotic antagonist EN-1639A (naltrexone) was studied in 37 heroin addicts and found to be clinically useful, with a low incidence of side effects, lack of toxicity, high degree of acceptability to the patient, and capacity to antagonize the euphoric effects of heroin for up to 72 hours after a single oral dose. These findings provide a basis for expanding studies of the clinical efficacy of naltrexone in the treatment of opiate dependence.