Depersonalization-derealization disorder occurs when you persistently or repeatedly have the feeling that you're observing yourself from outside your body or you have a sense that things around you aren't real, or both. Feelings of depersonalization and derealization can be very disturbing and may feel like you're living in a dream.
Many people have a passing experience of depersonalization or derealization at some point. But when these feelings keep occurring or never completely go away, it's considered depersonalization-derealization disorder. This disorder is more common in people who've had traumatic experiences.
Depersonalization-derealization disorder can be severe and may interfere with relationships, work and other daily activities. The main treatment for depersonalization-derealization disorder is talk therapy (psychotherapy), although sometimes medications also are used.