A narcissistic personality disorder is a condition where individuals have an amplified/augmented sense of their own importance and a continuing need for attention and admiration. These individuals feel that they are superior to others and have little or no regard to the feelings of others. However, behind this façade of supreme importance and mega confidence, these individuals are quite fragile, have poor self esteem and are vulnerable to the slightest criticism.
In general, these individuals have dramatic emotional behaviors believing that they are superior, and tend to exaggerate their achievements, claims and talents. In return, they do expect constant praise, following and admiration.
Most people with this personality take advantage of others and usually express disdain for others whom they feel are inferior. Jealously is a common trait found in these individuals and most have unrealistic goals in life. While they appear tough minded, they are fragile emotionally and tormented.
Narcissistic personality is not the same as being confident. Narcissistic individuals have unhealthy confidence and value others as inferior.
No one really knows why such a personality develops but is most likely related to a dysfunctional childhood. There are no drugs to treat such behavior; the narcissistic individual is usually treated with some type of behavior therapy but reshaping personality is quite difficult.
In the end most of these individuals end up abusing alcohol, drugs, develop depression, and have very difficult social relationships.