Opioid-induced anxiety transtorno is characterised by anxiety symptoms (e.g., apprehension or worry, fear, physiological symptoms of excessive autonomic arousal, avoidance behaviour) that develop during or soon after intoxicação com or abstinência from opioids. The intensity or duration of the symptoms is substantially in excess of anxiety symptoms that are characteristic of Opioid intoxicação or Opioid abstinência. The amount and duration of opioid uso must be capable of producing anxiety symptoms. The symptoms are not better explained by a primary mental transtorno (e.g., an Anxiety and Fear-Related transtorno, a Depressive transtorno com prominent anxiety symptoms), as might be the case if the anxiety symptoms preceded the onset of the opioid uso, if the symptoms persist for a substantial period of time after cessation of the opioid uso or abstinência, or if there is other evidence of a pre-existing primary mental transtorno com anxiety symptoms (e.g., a history of prior episodes not associated com opioid uso).