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People with narcissistic personality disorder are characterized by their persistent grandiosity, excessive need for admiration, and a disdain and lack of empathy for others.^[8][9] These individuals often display arrogance, a sense of superiority, and power-seeking behaviors.^[10] Narcissistic personality disorder is different from having a strong sense of self-confidence; people with NPD typically value themselves over others to the extent that they disregard the feelings and wishes of others and expect to be treated as superior regardless of their actual status or achievements.^[8][11] In addition, people with NPD may exhibit fragile egos, an inability to tolerate criticism, and a tendency to belittle others in an attempt to validate their own superiority.^[11]

According to the DSM-5, individuals with NPD have most or all of the following symptoms, typically without commensurate qualities or accomplishments:^[8][11]

1. Grandiosity with expectations of superior treatment from others
2. Fixated on fantasies of power, success, intelligence, attractiveness, etc.
3. Self-perception of being unique, superior and associated with high-status people and institutions
4. Needing constant admiration from others
5. Sense of entitlement to special treatment and to obedience from others
6. Exploitative of others to achieve personal gain
7. Unwilling to empathize with others’ feelings, wishes, or needs
8. Intensely envious of others and the belief that others are equally envious of them
9. Pompous and arrogant demeanor

NPD usually develops by adolescence or early adulthood.^[8] It is not uncommon for children and teens to display some traits similar to NPD, but these are typically transient without meeting full criteria for the diagnosis.^[11] True NPD symptoms are pervasive, apparent in various situations, and rigid, remaining consistent over time. The symptoms must be severe enough that they significantly impair the individual’s ability to develop meaningful relationships with others. Symptoms also generally impair an individual’s ability to function at work, school, or in other important settings. According to the DSM-5, these traits must differ substantially from cultural norms in order to qualify as symptoms of NPD.^[8]

Associated features

People with NPD tend to exaggerate their skills and accomplishments as well as their level of intimacy with people they consider to be high-status. Their sense of superiority may cause them to monopolize conversations^[11] and to become impatient or disdainful when others talk about themselves.^[8] In the course of a conversation, they may purposefully or unknowingly disparage or devalue the other person by overemphasizing their own success. When they are aware that their statements have hurt someone else, they tend to react with contempt and to view it as a sign of weakness.^[8] When their own ego is wounded by a real or perceived criticism, their anger can be disproportionate to the situation,^[11] but typically, their actions and responses are deliberate and calculated.^[8] Despite occasional flare-ups of insecurity, their self-image is primarily stable (i.e., overinflated).^[8]

To the extent that people are pathologically narcissistic, they can be controlling, blaming, self-absorbed, intolerant of others’ views, unaware of others’ needs and of the effects of their behavior on others, and insistent that others see them as they wish to be seen.^[8] Narcissistic individuals use various strategies to protect the self at the expense of others. They tend to devalue, derogate, insult, blame others and they often respond to threatening feedback with anger and hostility.^[12] Since the fragile ego of individuals with NPD is hypersensitive to perceived criticism or defeat, they are prone to feelings of shame, humiliation and worthlessness over minor or even imagined incidents.^[11] They usually mask these feelings from others with feigned humility, isolating socially or they may react with outbursts of rage, defiance, or by seeking revenge.^[8][9] The merging of the “inflated self-concept” and the “actual self” is seen in the inherent grandiosity of narcissistic personality disorder. Also inherent in this process are the defense mechanisms of denial, idealization and devaluation.^[13]

According to the DSM-5, “Many highly successful individuals display personality traits that might be considered narcissistic. Only when these traits are inflexible, maladaptive, and persisting and cause significant functional impairment or subjective distress do they constitute narcissistic personality disorder.”^[8] Although overconfidence tends to make individuals with NPD ambitious, it does not necessarily lead to success and high achievement professionally. These individuals may be unwilling to compete or may refuse to take any risks in order to avoid appearing like a failure.^[8][9] In addition, their inability to tolerate setbacks, disagreements or criticism, along with lack of empathy, make it difficult for such individuals to work cooperatively with others or to maintain long-term professional relationships with superiors and colleagues.^[