 My name is Sam Vaknin, and I am the author of Malignant St. Flava, Narcissism Revisited. The narcissist moods change abruptly in the wake of narcissistic injury. One can easily manipulate the moods of a narcissist by making a disparaging comment, by disagreeing with the narcissist, by criticizing him, by doubting his grandiosity or fantastic claims, and so on. Such moodshifts are therefore reactive. They are not provoked by fluctuations in the narcissist's body chemistry, for instance, blood sugar levels. They are not provoked by any absence or presence of a substance or a chemical in his brain. It is possible to reduce the narcissists to a state of rage and depression at any moment, simply by employing the above techniques of disparaging, disagreement, criticism, and above all, by ignoring him. The narcissist can be elated, even manic, and in a split second, following a narcissistic injury, he becomes depressed, sulking, or raging. And the opposite is also true. The narcissist can be catapulted from the bleakest despair to utter mania or at least to an increased and marked feeling of well-being. And this, by being provided with the flimsiest narcissistic supply, a modicum of attention, some adulation, affirmation, applause. So these swings between depression and elation are totally correlated to external events, narcissistic injury or narcissistic supply. And they are not correlated, and they are not cycles of hormones, enzymes, neurotransmitters, sugar, or other substances in the body. Admittedly, it is conceivable that some third unrelated problem causes all these things, some chemical imbalance in the brain, a metabolic disease such as diabetes, pathological narcissism, other mental health syndromes, all of these may be co-generated by, for instance, a group of genes, by a hidden common denominator. But this is probably unlikely. We know that certain medical conditions can activate the narcissistic defense mechanism. Chronic ailments are likely to lead to the emergence of narcissistic traits or a narcissistic personality style. Traumas such as brain injuries have been known to induce states of mind akin to full-blown personality disorders on a temporary level. Such narcissism, though, narcissism caused by a brain injury or by fluctuations in biochemical substances or by genetic factors, when such narcissism is reversible. It tends to be ameliorated or disappear altogether when the underlying medical problem has been successfully treated. Other disorders like bipolar disorder, previously known as mania depression, are characterized by mood swings that are not brought about by external events, endogenous. So it's an endogenous disease, not an exogenous one. But the narcissistic mood swings are strictly the result of external events as it perceives an interpretive, of course. So here we have it. There is a group of mental health disorders which are the clear outcome of internal fluctuations in body biochemicals. And there is pathological narcissism, narcissistic personality disorder, where mood swings are completely reactive and conditioned on external events. Narcissists are absolutely insulated from their emotions. They are emotionally flat or numb. The narcissist does not have pendular, cyclical mood swings on a regular, almost predictable basis from depression to euphoria or to mania, as is the case in biochemically induced mental disorders. Additionally, the narcissist goes through megacycles, which last months, sometimes years. This cannot, of course, be attributed to blood sugar levels or to dopamine and serotonin, secretions in the brain. The narcissistic personality disorder per se is not treated with medication. The underlying disorder is treated by one of the long-term psychodynamic or cognitive behavioral therapies. Other personality disorders and narcissism is usually comorbid, diagnosed with other disorders are treated separately, according to their own characteristics. But phenomena which are often associated with narcissistic personality disorder, such as depression or obsessive-compulsive behaviors, these are treated with medication. Rumors have it that SSRIs, such as Fluoxetine, known as Prozac, might have adverse effects if the primary disorder is narcissistic personality disorder. They sometimes lead to a serotonin syndrome, which includes agitation and exacerbates the rage attacks typical of a narcissistic. The use of SSRIs is associated at times with delirium in the emergence of a manic phase and even with psychotic microepisodes. It might not be recommended to treat narcissists with SSRIs. This is not the case with heterocyclics, MAO, and mood stabilizers, such as lithium. Blockers and inhibitors are regularly applied without discernible adverse side effects, as far as narcissistic personality disorder is concerned. Additionally, cognitive behavioral therapies are often used to treat attendant OCD, or obsessive-compulsive disorder, in depression. To summarize, not enough is known about the biochemistry of narcissistic personality disorder. There seems to be some vague link to serotonin, but no one knows for sure. There isn't a reliable, non-intrusive method to measure brain and central nervous system serotonin levels anyhow, so it is mostly guesswork at this stage. Thus, as of now, the typical and recommended treatment for pathological narcissism and its comorbid depression and obsessive-compulsive conduct is talk therapy, with one kind psychodynamic or another cognitive behavior. Anti-depressants can be used moderately, with SSRI being currently under critical scrutiny.