disorder, the symptoms should not occur in th e context of another dissociative disorder,
such as dissociative identity disorder. Differentiation from dissociative amnesia and con-
version disorder (functional neurological sy mptom disorder) is simpler, as the symptoms
of these disorders do not overlap with those of depersonalization/derealization disorder. 
Anxiety disorders. Depersonalization/derealization is one of the symptoms of panic at-
tacks, increasingly common as panic attack severity increases. Therefore, depersonal-
ization/derealization disorder should not be diagnosed when the symptoms occur only
during panic attacks that are part of panic disorder, social anxiety disorder, or specific
phobia. In addition, it is not uncommon for depersonalization/derealization symptoms
to first begin in the context of new-onset pani c attacks or as panic disorder progresses and
worsens. In such presentations, the diagno sis of depersonalization/ derealization disorder
can be made if 1) the depersonalization/de realization component of  the presentation is
very prominent from the start, clearly exceed ing in duration and intensity the occurrence
of actual panic attacks; or 2) the depersona lization/derealization continues after panic dis-
order has remitted or has be en successfully treated. 
Psychotic disorders. The presence of intact reality testing specifically regarding the
depersonalization/derealization symptoms is essential to differentiating depersonal-
ization/derealization disord er from psychotic disorder s. Rarely, positive-symptom
schizophrenia can pose a diagnostic challenge when nihilistic delusions are present. For
example, an individual may complain that he or she is dead or the world is not real; this
could be either a subjective experience that the individual knows is not true or a delusional
conviction.