Which antipsychotic is noted for its serious side effect of tardive dyskinesia?

Tardive dyskinesia is a significant and often irreversible movement disorder typically associated with long-term use of typical antipsychotics. Chlorpromazine, being one of the first-generation antipsychotics, is known for its higher propensity to cause this side effect. This class of medication primarily blocks dopamine D2 receptors, which is how they exert their antipsychotic effects. However, this same mechanism can lead to the development of movement disorders, particularly after prolonged treatment.

In comparison, the other antipsychotics listed—risperidone, clozapine, and quetiapine—are newer agents that are often classified as atypical antipsychotics. While they can also lead to movement disorders, they tend to have a lower risk of tardive dyskinesia than typical antipsychotics. Among atypicals, clozapine is particularly noted for having a different side effect profile, including agranulocytosis, rather than tardive dyskinesia. Risperidone and quetiapine may cause other side effects but are less associated with tardive dyskinesia compared to chlorpromazine.

Therefore, chlorpromazine is correctly identified as the antipsychotic