While the pathophysiology of the negative symptoms is still not known, the development of positive symptoms are thought to be related to a hyperactive dopamine system.5 Additionally, mood symptoms can be observed in schizoaffective disorder where an individual can display depression, dysphoria, or hopelessness as a hallmark feature.
For the most part, the symptoms of psychotic disorders can differ from one person to the other, though the most commonly observed ones are delusions and hallucinations. The exact cause of psychotic disorders is still not known, but it is theorized that it is related to a variety of factors including genetic, medical, and environmental.5
While the origins of psychotic disorders still remains elusive, researchers and scientists have been able to develop pharmacotherapies that have been instrumental in targeting the core symptoms of specific psychotic disorders whether they are predominately negative, positive, cognitive, or mood symptoms that disturb a person’s ability to lead a normal life.
When it comes to the use of antipsychotics, they are to be started as soon as signs of psychosis are observed in an individual so a full-blown psychotic episode may be avoided through an early intervention.5 Biomedically, antipsychotics are thought to exert their antipsychotic effect by reducing dopamine transmission centrally which is related to the blockage of postsynaptic D2 receptors in the mesolimbic pathway and possibly the mesocortical pathway of the brain.3,4, 5
For antipsychotic therapy, consideration has to be given to the side effect profile and neurotransmitters that are specifically targeted by either the typical (first-generation) or atypical (second-generation) antipsychotics. The typical antipsychotic chlorpromazine was the first antipsychotic to be used and other atypicals, such as haloperidol, thiordazine, and perphenazine, followed suit. Then came the second-generation antipsychotics (e.g. clozapine, olanzapine, risperidone, quetiapine, ziprasidone, aripiprazole, and more recently, paliperidone, iloperidone, and asenapine), which have a greater serotonin (5HT)/dopamine (DA) ratio compared to the typical antipsychotics.4