Okay, let's tackle this question about extrapyramidal syndrome (EPS) side effects. The question is asking which drugs cause EPS. First, I need to recall what EPS is. EPS refers to movement disorders caused by dopamine receptor blockade, usually D2 receptors in the basal ganglia. Common drugs that cause this are antipsychotics, especially first-generation ones like haloperidol or chlorpromazine. They block dopamine receptors in the nigrostriatal pathway, leading to symptoms like akathisia, dystonia, parkinsonism, or tardive dyskinesia.

Now, the options are missing, but the correct answer is likely an antipsychotic. Let's assume the options are typical antipsychotics versus atypical ones. For example, if the options are A. Chlorpromazine, B. Olanzapine, C. Risperidone, D. Quetiapine. Then the correct answer would be A. Chlorpromazine because first-gen antipsychotics are more likely to cause EPS due to higher D2 blockade. The atypical ones (B, C, D) have lower EPS rates because they have more 5-HT2A antagonism and less D2 blockade.

Wait, but the user didn't provide the actual options. Hmm, maybe the original question had specific drugs. Let me think of common options. If the correct answer is a typical antipsychotic, then the explanation would focus on dopamine antagonism. If it's a drug that blocks dopamine receptors, like metoclopramide (a dopamine antagonist used for GI), that could also cause EPS. But antipsychotics are the main ones.

The core concept is that EPS occurs due to dopamine receptor blockade, especially in the basal ganglia. The correct answer would be a drug known for high D2 receptor antagonism. The wrong options might include drugs that don't block dopamine receptors or are less likely to do so. For example, SSRIs don't cause EPS because they affect serotonin. Antihistamines might cause sedation but not EPS. Beta-blockers are for heart issues.

So, the clinical pearl here is that first-generation antipsychotics and dopamine antagonists like metoclopramide are high on EPS risk, while atypical antipsychotics are lower risk. Students should remember that EPS is a red flag for dopamine blockade and is more common with typical antipsychotics.

**Core Concept**
Extrapyramidal syndrome (EPS) is a movement disorder caused by dopamine receptor (D2) antagonism in the basal ganglia, predominantly affecting the nigrostriatal pathway. It is classically associated with first-generation antipsychotics and dopamine-blocking antiemetics like metoclopramide.

**Why the Correct Answer is Right**
First-generation antipsychotics (e.g., haloperidol, chlorpromazine) irreversibly block dopamine D2 receptors in the basal ganglia, disrupting motor control pathways. This leads to acute dystonia, akathisia, parkinsonism, or tardive dyskinesia. Dopamine antagonism in the nigrostriatal pathway reduces inhibitory GABAergic tone, causing overactivity of the direct motor pathway and EPS symptoms.

**Why Each Wrong Option is Incorrect**
**Option A:** Antidepressants like SSRIs/SNRIs do not block dopamine D2 receptors and

✓ Correct Answer: A. Haloperidol