opioid use disorder
in DSM–5, a diagnostic category reflecting disordered use of natural opioids (e.g., morphine), semisynthetic derivatives (e.g., heroin), and synthetic compounds with morphinelike effects (e.g., oxycodone). It combines DSM–IV–TR’s separate abuse and dependence diagnoses for these substances, thereby removing opioid abuse and opioid dependence as distinct entities. Mild, moderate, and severe cases of opioid use disorder are determined according to the number of symptoms that individuals using these substances may present (e.g., craving; drug-seeking behavor; social and other dysfunction caused by opioid use; tolerance; withdrawal, etc.); the number ranges from a minimum of two symptoms for mild cases to more than six for severe.