Journal of Addiction Research & Therapy
Open Access

Abstract

Background: Lofexidine, an alpha-2 adrenergic receptor agonist, has been approved in the United Kingdom for the treatment of opioid withdrawal symptoms. Many research studies have demonstrated the efficacy and safety of lofexidine comparing with placebo, clonidine, methadone, buprenorphine. However none of these studies has compared lofexidine with diazepam in managing heroin withdrawal syndrome. This study looks at the efficacy of lofexidine versus diazepam on reducing anxiety symptoms during inpatient detoxification. Method: This is a randomised double-blind investigator initiated trial in National Addictions Management Service (NAMS), Singapore. Maudsley Addiction Profile (MAP) containing measurements on the severity of anxious and depressed moods was assessed every 3 days after admission (on days 3, 6, 9 and 12) by the delegated researcher. Subjects received either standard treatment diazepam or the trial medication lofexidine up to 10 days followed by 4 days continuous psychological education during NAMS inpatient detoxification programme. Initial dosage of lofexidine and diazepam started from 0.8 mg and 10 mg respectively, per day in divided doses. The peak dosage of lofexidine and diazepam were 2.2 mg and 15 mg (on day 3, 4) respectively. The subjects in both groups subsequently received the tapering doses till day 10. CBT based psychological intervention were provided throughout the whole study period. Results: Total 111 patients with diagnosis of heroin dependence (DSM-IV-TR) were randomized to the trial, 56 in lofexidine group and 55 in diazepam group. The severity of anxiety symptoms in MAP such as â�?�?feeling tenseâ�?, â�?�?suddenly scared for no reasonâ�?, â�?�?feeling fearfulâ�?, â�?�?nervousness of shakiness insideâ�? and â�?�?spells of terrorâ�? or â�?�?panicâ�? reduced in both treatment groups over time during the study period. There were no statistical differences comparing these anxiety symptoms between lofexidine group and diazepam groups. Discussion: Diazepam is prescribed as the standard pharmacological treatment in the management of opioid withdrawal syndrome in NAMS. However, itâ�?�?s addictive pharmacological profile limits its usage for opioid dependence. The results suggest that lofexidine, a non-opiate, non-addictive alpha-2-agonist could be an alternative medication in assisting opioid detoxification in Singapore.

Biography

Song Guo is a Senior Consultant Psychiatrist and the Head of Research of the Addiction Medicine Department and National Addictions Management Service of Institute of Mental Health Singapore, with a joint position as Adjunct Assistant Professor at Duke-NUS Graduate Medical School. He holds a PhD in Psychopharmacology and has practiced in Addictions Medicine since 1990, including serving as the Director of the National Drug Dependence Treatment Centre, Beijing (2003-2004). His interests are in the areas of translational clinical studies and treatment outcome monitoring.