Animal studies trigger new insights on the use of methadone maintenance

Abstract

Background: Although steady-state methadone (SSM) treatment is mainly used for opioid addiction, some clinical studies indicate that it also reduces cocaine abuse in opioid-dependent individuals. Objective/methods: To present evidence suggesting that SSM may be useful in the treatment of cocaine addiction without pre-existing opioid dependence. We review studies in animals investigating the effects of SSM on behaviors motivated by cocaine and on cocaine-induced alterations of genes expression in the rat brain. Conclusion: SSM reduces cocaine intake, blocks cocaine seeking and normalizes expression of genes known to regulate cocaine seeking. These findings suggest that SSM could be an effective pharmacological agent to assist cocaine detoxification and prevention of relapse to cocaine abuse in individuals not co-dependent on opioid.

Keywords::

• animals
• cocaine
• high-dose
• hypothalamic-pituitary-adrenal axis
• methadone
• mRNA
• μ-opioid receptor