Review Question - QID 108958

A 73-year-old male presents to his primary care provider for a tremor in his right hand. The patient reports that the shaking started a few months ago in his hand but that he is worried that it has spread to his left hand as well. He reports that the shaking is worse when he is sitting still or watching television and improves as he goes about his daily activities. He struggles to perform some acts of daily living. The patient has a past medical history of hypertension, hyperlipidemia, and diabetes mellitus. His home medications are hydrochlorothiazide, lisinopril, and atorvastatin. He works as an accountant and drinks 1-2 beers per week. He has a 15-pack-year smoking history but quit 10 years ago. His temperature is 98.6°F (37°C), blood pressure is 142/94 mmHg, pulse is 82/min, and respirations are 14/min. On physical exam, the patient has bilateral hand tremors with a frequency of 4-5 Hz. The tremor improves on finger-to-nose testing. His upper extremities also display a mild resistance to passive movement and he has 2+ reflexes throughout. He has no gait abnormalities. He scores 29/30 on the mini-mental state examination (MMSE). This patient should most likely be started on medication with which of the following effects?