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

BACKGROUND: 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 who remained and treatment and did not relapse, and between the last measure before dropout with the same measure for those remaining in treatment. RESULTS: Depression, anxiety, and anhedonia were elevated at baseline but reduced to normal within the first 1-2 months for patients who remained in treatment and did not relapse. Other than a slight increase in two anxiety measures at week two, there were no significant between-group differences prior to treatment dropout. CONCLUSION: These data do not support concerns that naltrexone treatment of opioid dependence increases craving, depression, anxiety or anhedonia.

Randomized trial of long-acting sustained-release naltrexone implant vs oral naltrexone or placebo for preventing relapse to opioid dependence.

CONTEXT Sustained-release naltrexone implants may improve outcomes of nonagonist treatment of opioid addiction. OBJECTIVE To compare outcomes of naltrexone implants, oral naltrexone hydrochloride, and nonmedication treatment. DESIGN Six-month double-blind, double-dummy, randomized trial. SETTING Addiction treatment programs in St Petersburg, Russia. PARTICIPANTS Three hundred six opioid-addicted patients recently undergoing detoxification. INTERVENTIONS Biweekly counseling and 1 of the following 3 treatments for 24 weeks: (1) 1000-mg naltrexone implant and oral placebo (NI+OP group; 102 patients); (2) placebo implant and 50-mg oral naltrexone hydrochloride (PI+ON group; 102 patients); or (3) placebo implant and oral placebo (PI+OP group; 102 patients). MAIN OUTCOME MEASURE Percentage of patients retained in treatment without relapse. RESULTS By month 6, 54 of 102 patients in the NI+OP group (52.9%) remained in treatment without relapse compared with 16 of 102 patients in the PI+ON group (15.7%) (survival analysis, log-rank test, P < .001) and 11 of 102 patients in the PI+OP group (10.8%) (P < .001). The PI+ON vs PI+OP comparison showed a nonsignificant trend favoring the PI+ON group (P = .07). Counting missing test results as positive, the proportion of urine screening tests yielding negative results for opiates was 63.6% (95% CI, 60%-66%) for the NI+OP group; 42.7% (40%-45%) for the PI+ON group; and 34.1% (32%-37%) for the PI+OP group (P < .001, Fisher exact test, compared with the NI+OP group). Twelve wound infections occurred among 244 implantations (4.9%) in the NI+OP group, 2 among 181 (1.1%) in the PI+ON group, and 1 among 148 (0.7%) in the PI+OP group (P = .02). All events were in the first 2 weeks after implantation and resolved with antibiotic therapy. Four local-site reactions (redness and swelling) occurred in the second month after implantation in the NI+OP group (P = .12), and all resolved with antiallergy medication treatment. Other nonlocal-site adverse effects were reported in 8 of 886 visits (0.9%) in the NI+OP group, 4 of 522 visits (0.8%) in the PI+ON group, and 3 of 394 visits (0.8%) in the PI+ON group; all resolved and none were serious. No evidence of increased deaths from overdose after naltrexone treatment ended was found. CONCLUSIONS The implant is more effective than oral naltrexone or placebo. More patients in the NI+OP than in the other groups develop wound infections or local irritation, but none are serious and all resolve with treatment. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00678418.