The DSM 5 diagnostics for the dissociative Disorder now known as depersonalization/derealization disorder is....

Depersonalization/derealization Disorder 300.6 (F48.1)

A the presence of persistant or recurrent experiences of depersonalization, derealization or both:

1. Depersonalization: Experiences of unreality, detachment or being outside observer with respect to ones thoughts, feelings, sensations, body or actions (e.g perceptual alterations, distorted sense of time, unreal or absent self, emotional or physical numbing)

2. Derealization: experiences of unreality or detachment with respect to surroundings (e.g. individuals or objects are experienced as unreal dreamlike, foggy, lifeless or visually distorted)

B. During the depersonalization or derealization experiences, reality testing remains intact.

C. the symptoms cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.

D. the disturbance is not attributable to the physiological effects of a substance (e.g. a drug of abuse, medication) or other medical condition. (e.g. Seizures)

E. The disturbance is not better explained by another mental disorder such as schizophrenia, panic disorder, major depressive disorder, acute stress disorder, post traumatic stress disorder or other dissociative disorder.

the DSM 5 also goes through the categories of diagnostic features, associated features supporting diagnosis, prevalence, development and course, Risk and Prognosis Factors, Cultural Related Diagnostic issues, Functional consequences of depersonalization/derealization disorder, differential diagnosis, and comorbidity.