Narcissism, or narcissistic personality disorder, may cause patients to have an exaggerated sense of self-importance, thoughts of superiority, a requirement for constant admiration and a sense of entitlement, according to Mayo Clinic. People with this disorder may handle criticism poorly and may harbor secret feelings of shame.
Patients who have narcissistic personality disorder often portray themselves as being better than their peers, states Mayo Clinic. These patients tend to perceive themselves as superior and often believe that they deserve special treatment. If they do not get special treatment from their friends and family members, then they may become angry and despondent.