Background

Withdrawal is a necessary step prior to drug‐free treatment. It may also represent the end point of long‐term substitution treatment.

Objectives

To assess the effectiveness of interventions involving the use of alpha2 adrenergic agonists to manage opioid withdrawal.

Search methods

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2007), MEDLINE (January 1966‐September 2007), EMBASE (January 1985‐September 2007), PsycINFO (October 2007) and reference lists of the articles. We also contacted manufacturers in the field.

Selection criteria

Controlled trials comparing alpha2 adrenergic agonists with reducing doses of methadone, symptomatic medications or placebo, or comparing different alpha2 adrenergic agonists to modify the signs and symptoms of withdrawal in participants who were primarily opioid dependent.

Data collection and analysis

One reviewer assessed studies for inclusion and undertook data extraction. Inclusion decisions and the overall process were confirmed by consultation between all four reviewers.

Main results

Twenty‐two studies, involving 1709 participants, were included. Eighteen were randomised controlled trials; for the remaining studies allocation was by participant choice in two, one used alternate allocation and in one the method of allocation was unclear.

Twelve studies compared a treatment regime based on an alpha2 adrenergic agonist with one based on reducing doses of methadone.

Diversity in study design, assessment and reporting of outcomes limited the extent of quantitative analysis.

For the comparison of alpha2 adrenergic agonist regimes with reducing doses of methadone, there were insufficient data for statistical analysis, but withdrawal intensity appears similar to or marginally greater with alpha2 adrenergic agonists, while signs and symptoms of withdrawal occur and resolve earlier in treatment. Participants stay in treatment longer with methadone. No significant difference was detected in rates of completion of withdrawal with adrenergic agonists compared to reducing doses of methadone, or clonidine compared to lofexidine. Clonidine is associated with more adverse effects (low blood pressure, dizziness, dry mouth, lack of energy) than reducing doses of methadone. Lofexidine does not reduce blood pressure to the same extent as clonidine, but is otherwise similar to clonidine.

Authors' conclusions

No significant difference in efficacy was detected for treatment regimes based on the alpha2 adrenergic agonists clonidine and lofexidine, and those based on reducing doses of methadone over a period of around 10 days, for the management of withdrawal from heroin or methadone.