Narcissistic personality disorder (NPD) is a personality disorder with a long-term pattern of abnormal behavior characterized by exaggerated feelings of self-importance, excessive need for admiration, and a lack of empathy.[2][3] Those affected often spend much time thinking about achieving power or success, or on their appearance.[3] They often take advantage of the people around them.[3] The behavior typically begins by early adulthood, and occurs across a variety of social situations.[3] The cause of narcissistic personality disorder is unknown.[4] It is a personality disorder classified within cluster B by the Diagnostic and Statistical Manual of Mental Disorders (DSM).[3] Diagnosis is made by a healthcare professional interviewing the person in question.[2] The condition needs to be differentiated from mania and substance use disorder.[3] Treatments have not been well studied.[2] Therapy is often difficult, as people with the disorder frequently do not consider themselves to have a problem.[2] About one percent of people are believed to be affected at some point in their life.[4] It appears to occur more often in males than females and affects young people more than older people.[2][3] The personality was first described in 1925 by Robert Waelder, and the term NPD came into use in 1968.[5] https://en.wikipedia.org/wiki/Narcissistic_personality_disorder
