Which antipsychotic is noted for the highest risk of extrapyramidal symptoms (EPS)?

Risperdal (Risperidone) is indeed noted for having the highest risk of extrapyramidal symptoms (EPS) among the antipsychotic medications listed. EPS are drug-induced movement disorders that can include symptoms such as tremors, rigidity, bradykinesia, and tardive dyskinesia.

The mechanism of action for Risperdal involves a significant blockade of dopamine D2 receptors, which is closely associated with the development of EPS. While some newer atypical antipsychotics carry a lower risk of EPS compared to older medications, Risperdal's potency in blocking dopamine receptors makes it more likely to induce these side effects.

In contrast, other antipsychotics mentioned have varying mechanisms and receptor profiles that contribute to a lower incidence of EPS. For example, Geodon (Ziprasidone) and Zyprexa (Olanzapine) have a more favorable side effect profile regarding movement disorders, largely due to their effects on serotonin receptors and a relatively lower affinity for dopamine receptor blockade. Abilify (Aripiprazole) is also associated with a lower risk of EPS, as it acts as a partial agonist at dopamine receptors, which can mitigate the risk of movement disorders while still