Disorders due to Substance Use: Opioids and Opioid Addiction

This chapter begins with an overview of opioid-related disorders (OUDs) and how they are defined in the International Classification of Disease Version 11 (ICD-11) and Diagnostic and Statistical Manual of the American Psychiatric Association (DSM-5). It provides a table of commonly used opioids and their routes of administration, medical uses, and duration of effects, describes the ICD-11 and DSM-5 definitions of opioid use disorders, describes opioid intoxication and withdrawal, opioid-related psychiatric disorders, and reviews their epidemiology, clinical presentations, and laboratory findings. It describes detoxification and maintenance treatments, their outcomes, comments on the variability in regulatory structures under which maintenance treatments are provided, and gives a few examples of regulatory changes that have been made to improve access to agonist-based maintenance treatment. It discusses the problem of treatment dropout and the development of extended release formulations to reduce it. It ends with an overview of psychosocial treatments, harm reduction, medically supervised injection, and two clinical vignettes.