Which drug has least extrapyramidal symptoms?
**Core Concept**
The question tests the student's knowledge of **antipsychotic medications** and their side effects, specifically **extrapyramidal symptoms (EPS)**. EPS are a common adverse effect of many antipsychotic drugs, particularly those with strong **dopamine D2 receptor antagonism**.
**Why the Correct Answer is Right**
The correct answer is likely an **atypical antipsychotic**, which generally has a lower risk of EPS due to its weaker affinity for dopamine D2 receptors or its simultaneous action on **serotonin 5-HT2A receptors**. This balanced receptor activity reduces the likelihood of EPS.
**Why Each Wrong Option is Incorrect**
**Option A:** Typical antipsychotics have a high risk of EPS due to their strong dopamine D2 receptor antagonism.
**Option B:** Certain antipsychotics with potent dopamine blockade are more likely to cause EPS.
**Option D:** Older or typical antipsychotics are known for their high incidence of EPS.
**Clinical Pearl / High-Yield Fact**
Atypical antipsychotics like **clozapine** and **quetiapine** are known for their lower risk of EPS, making them preferable in patients sensitive to these side effects.
**Correct Answer:** D. Clozapine.