A 72-year-old man is brought to the emergency department due t | Uworld | Step 1

A 72-year-old man is brought to the emergency department due to involuntary movements of his right arm that started several hours ago. He was watching television when his arm "threw the remote control across the room." His past medical history is significant for long-standing hypertension and diabetes mellitus. The patient does not use alcohol, tobacco, or illicit drugs. Physical examination shows wild, large-amplitude, flinging movements affecting the proximal muscles of his right arm.