"Depersonalization/derealization disorder is a type of dissociative disorder that consists of persistent or recurrent feelings of being detached (dissociated) from one’s body or mental processes, usually with a feeling of being an outside observer of one’s life (depersonalization), or of being detached from one's surroundings (derealization). The disorder is often triggered by severe stress. Diagnosis is based on symptoms after other possible causes are ruled out. Treatment consists of psychotherapy plus drug therapy for any comorbid depression and/or anxiety."