Anhedonia, depression, anxiety, and craving in opiate dependent patients stabilized on oral naltrexone or an extended release naltrexone implant

ABSTRACTBackground: Naltrexone is a μ-opioid receptor antagonist that blocks opioid effects. Craving, depression, anxiety, and anhedonia are common among opioid dependent individuals and concerns have been raised that naltrexone increases them due to blocking endogenous opioids. Here, we present data that address these concerns. Objective: Assess the relationship between affective responses and naltrexone treatment. Methods: Opioid dependent patients (N = 306) were enrolled in a three cell (102ss/cell) randomized, double blind, double dummy, placebo-controlled 6-month trial comparing extended release implantable naltrexone with oral naltrexone and placebo (oral and implant). Monthly assessments of affective responses used a Visual Analog Scale for opioid craving, the Beck Depression Inventory, Spielberger Anxiety Test, and the Ferguson and Chapman Anhedonia Scales. Between-group outcomes were analyzed using mixed model analysis of variance (Mixed ANOVA) and repeated measures and the Tukey test for those w...