APA Dictionary of Psychology

a problematic and recurrent pattern of opioid use, characterized by tolerance, withdrawal, craving, and persistent use despite failure to fulfill role obligations and problems resulting from opioid use, included in DSM-5 and DSM-5-TR. Opioids include natural opioids (e.g., morphine, codeine), semisynthetic derivatives (e.g., heroin, oxycodone), and synthetic compounds with morphinelike effects (e.g., methadone, fentanyl). 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. Opioid use disorder combines DSM–IV–TR’s separate abuse and dependence diagnoses for these substances, thereby removing opioid abuse and opioid dependence as distinct entities.