Which of the following is an example of a first-generation antipsychotic?

• A. Risperidone
• B. Olanzapine
• C. Haloperidol
• D. Clozapine

Answer: (C)

First-generation antipsychotics are the older class that primarily blocks dopamine D2 receptors in the brain. They’re effective for positive symptoms of psychosis but come with a higher risk of extrapyramidal side effects. Haloperidol is a classic example of this group, known for strong D2 blockade and a higher likelihood of EPS like akathisia, parkinsonism, and dystonia. The other drugs listed are second-generation (atypical) antipsychotics, which also block serotonin receptors and tend to have a lower EPS risk but more metabolic side effects. Risperidone and olanzapine are SGAs, and clozapine is a well-known SGA used for treatment-resistant cases. So haloperidol fits the first-generation profile.