<prompt> A 25 year old man with a psychotic illness, was treated with haloperido130mgday. On the third day, he developed pacing, and inability to sit still in one place. The medication likely to be helpful is -PhenytoinPropranololMethylphenidateTrihexyphenedyl  <response>: Restlessness inability to sit still and pacing suggests the diagnosis of Akathesia.The drug of choice for Akathesia is one of the β-blocker. 