"Narcissistic personality disorder is one of several types of personality disorders. Personality disorders are conditions in which people have traits that cause them to feel and behave in socially distressing ways, limiting their ability to function in relationships and other areas of their life, such as work or school.
If you have narcissistic personality disorder, you may come across as conceited, boastful or pretentious. You often monopolize conversations. You may belittle or look down on people you perceive as inferior. You may feel a sense of entitlement — and when you don't receive special treatment, you may become impatient or angry. You may insist on having "the best" of everything — for instance, the best car, athletic club or medical care.
At the same time, you have trouble handling anything that may be perceived as criticism. You may have secret feelings of insecurity, shame, vulnerability and humiliation. To feel better, you may react with rage or contempt and try to belittle the other person to make yourself appear superior. Or you may feel depressed and moody because you fall short of perfection.
Many experts use the criteria in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), published by the American Psychiatric Association, to diagnose mental conditions. This manual is also used by insurance companies to reimburse for treatment.
DSM-5 criteria for narcissistic personality disorder include these features:
Having an exaggerated sense of self-importance
Expecting to be recognized as superior even without achievements that warrant it
Exaggerating your achievements and talents
Being preoccupied with fantasies about success, power, brilliance, beauty or the perfect mate
Believing that you are superior and can only be understood by or associate with equally special people
Requiring constant admiration
Having a sense of entitlement
Expecting special favors and unquestioning compliance with your expectations
Taking advantage of others to get what you want
Having an inability or unwillingness to recognize the needs and feelings of others
Being envious of others and believing others envy you
Behaving in an arrogant or haughty manner
Although some features of narcissistic personality disorder may seem like having confidence, it's not the same. Narcissistic personality disorder crosses the border of healthy confidence into thinking so highly of yourself that you put yourself on a pedestal and value yourself more than you value others."
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