A double-blind randomized placebo-controlled study of the efficacy of the combined treatment with naltrexone and guanfacine for relapse prevention in opiate dependence

Abstract

Objective. Authors studied the effect of α-2-adrenoreceptor agonist guanfacine on replace prevention in opiate addicts. Material and methods. Three hundred and one recently detoxified opiate addicts were randomized under the double-blind double-dummy conditions into one of four treatment groups: naltrexone 50 mg/day + guanfacine 1 mg/day (N+G), naltrexone + guanfacine placebo (N+GP), naltrexone placebo + guanfacine (NP+G), and double placebo (NP+GP). The primary outcome was retention in treatment. The secondary outcomes were perceived stress (Perceived Stress Scale) and craving. Results. At the end of six months, 20 (26.7%) patients in the N+G group and 15 (19.7%) (p=0.26 to N+G) in N+GP group were retained in treatment compared to 5 (6.7%) in the NP+G group (p=0.002 to N+G group and p=0.017 to N+GP group) and 8 (10.7%) in the double placebo group (p=0.013 to N+G group). There is no significant difference in retention between the N+G group and N+GP group at the end of treatment. Conclusion. Guanfacine had significant craving and stress reducing effect. Naltrexone was more effective than placebo for relapse prevention in opioid dependent patients. The efficacy of the combination of naltrexone and guanfacine was comparable to naltrexone alone. Guanfacine moderately reduced both stress and craving.