From the listed antipsychotics, which is a typical (first-generation) agent?

• A. Chlorpromazine
• B. Clozapine
• C. Olanzapine
• D. Quetiapine

Answer: (A)

The main idea is distinguishing typical (first-generation) from atypical (second-generation) antipsychotics based on how they work and the side effects they cause. Chlorpromazine is a classic example of a typical antipsychotic; it primarily blocks dopamine D2 receptors and was developed as one of the early agents in this class. Because of this D2 blockade, typical antipsychotics tend to have a higher risk of extrapyramidal symptoms and tardive dyskinesia, especially at higher doses, and they can also produce other receptor-mediated effects like sedation and anticholinergic or orthostatic symptoms depending on potency. The other drugs listed—clozapine, olanzapine, and quetiapine—are atypical antipsychotics. They still affect dopamine but also strongly antagonize serotonin 5-HT2A receptors and generally have a lower risk of EPS, though they carry other important risks (clozapine with agranulocytosis, and olanzapine and quetiapine with metabolic side effects). Therefore, chlorpromazine is the typical antipsychotic among these options.