There is no large prospective cohort studies using different therapeutic doses and standardized distal outcomes, however there is a fair amount of evidence on the effectiveness of methadone as a long-term treatment for the addiction to opiates. Strengths include less illegal drug use, decreased criminal activity and better general functioning. Also physical and mental health seems to be more preserved and recovered. Since patients undergoing methadone treatment exhibit diminished likelihood of suffering from cardiovascular conditions, HIV, HCV, HBV and other infections, and lesser psychiatric comorbidity. This Editorial intends to define and guide the therapeutic statement to address the management of persons with opiate abuse or dependence. These proposals have been grounded in the main long-term studies, systematic analysis and meta-analytic approaches on the effectiveness of methadone. Thereby it is recommended, with the maximum level of evidence, methadone maintenance treatments in spite of its weaknesses (ie. Toxicity, cardiovascular risk, sedation problems and cognitive impairment), considering the clinical history, general health status, and willingness and preferences of the patient.