Antipsychotic drugs remain the mainstay for the treatment of schizophrenia. The treatment is concerned with both the acute illness and chronic disability. The main therapeutic purpose is to alleviate the symptoms of schizophrenia (antipsychotic drugs are far more effective in relieving positive symptoms than negative symptoms) and to prevent relapse. The most successful results can be achieved through the combination of antipsychotic drugs and various psychological interventions.



A clear division has been made between antipsychotic drugs. Initially developed agents are termed first generation or typical antipsychotics, whereas, the more recently developed drugs are referred to as second generation or atyptical antipsychotic drugs.

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In comparison to the typical antipsychotics, atypical antipsychotics have a reduced likelihood of causing involuntary movement disorders, which are also known as extrapyramidal side effects (EPS). Furthermore, another characteristic of atypical antipsychotic drugs is the increased efficacy against both positive and negative symptoms of schizophrenia comparative to typical drugs.



Antipsychotic drugs share the property of being highly potent dopamine receptor antagonists and this action is known to account for their antipsychotic activity. Most antipsychotic drugs have a strong affinity for dopamine D2 receptors, which seems to account for both their therapeutic action and their tendency to produce EPS. Receptor imaging studies suggest that the therapeutic efficacy of antipsychotic drugs is attained when D2 receptor occupancy reaches approximately 80%.