Methadone at tapered doses for the management of opioid withdrawal

Abuse of opioid drugs and dependence on them causes major health and social issues that include transmission of HIV and hepatitis C, increased crime and costs for health care and law enforcement, family disruption and lost productivity. Addicts, particularly those aged 15 to 34 years, are also at higher risk of death. Managed withdrawal (or detoxification) is used as the first step in treatment. Withdrawal symptoms include anxiety, chills, muscle pain (myalgia) and weakness, lethargy and drowsiness and various pharmacological agents can be used to reduce them. Persisting sleep disturbances and drug craving can continue for weeks and months after detoxification and often lead to relapse to opioid use. The number of addicts who complete detoxification tends to be low, and rates of relapse to opioid use following detoxification are high.
For a tapered dose treatment, illicit opioids are substituted with methadone or another agent under medical supervision in decreasing doses. The review authors searched the medical literature and identified 16 controlled trials involving 1187 adult opioid users in various countries. Trial participants were randomised to receive methadone or another pharmacological treatment over 3 to 30 days. The other treatments were adrenergic agonists including clonidine (11 studies), opioid agonists such as buprenorphine and LAAM (four studies) and chlordiazepoxide (one study). In the one study that compared methadone with placebo, withdrawal symptoms were more severe and more drop outs were found in the placebo group. The methadone starting dose ranged from 20 to 58 mg/day (mean 29 mg/day). Withdrawal symptoms were reduced with methadone but the majority of people relapsed to heroin use. There was no clear difference in completion of treatment or abstinence at follow up with the different agents. The results indicate that the medications used in the included studies are similar in terms of overall effectiveness although symptoms experienced by participants differed according to the medication used and the program adopted. Treatment with adrenergic agonists was associated with lower mean blood pressure (postural hypotension) than with methadone, from five trials.