The goal of this chapter is to show the reader a systematic approach to the assessment and treatment of aggression and violence arising from psychosis and a review of evidence-based pharmacological interventions for aggression and violence arising from impulsivity in the context of traumatic brain injury or neurocognitive disorder. In turn, we consider an algorithmic approach to the assessment and treatment of psychotically driven aggression and violence, the approach to treatment-resistance in schizophrenia spectrum disorders, data-supported treatment of aggression and violence related to traumatic brain injury, and, finally, data-supported pharmacological treatment of aggression and violence in the context of major neurocognitive disorder.

Nearly three times as many people detained in a jail have a serious mental illness (SMI) when compared to community samples. Once an individual with SMI gets involved in the criminal justice system, they are more likely than the general population to stay in the system, face repeated incarcerations, and return to prison more quickly when compared to their nonmentally ill counterparts.

In community settings, the principle barriers to independent living, stable relationships, and gainful employment arise from the negative and cognitive symptom domains of schizophrenia spectrum disorders., In contrast, the positive symptoms of psychosis often are the gateway (e.g. via persecutory delusion associated with anger) to arrest and criminalization for the mentally ill. Since the clinical discovery of chlorpromazine in 1952, dopamine antagonism in the mesolimbic dopamine circuit has been central to treating the positive symptoms of psychosis. The hyperactivity of the mesolimbic circuit and the normalizing effects of the dopamine antagonist antipsychotics are illustrated in Figure 18.1.