A 66-year old man comes to the physician for a 3-month history of falls. He has coronary artery disease, atrial fibrillation, type II diabetes mellitus, and osteoporosis. He takes metformin, verapamil, alendronate, metoclopramide, and lisinopril. Physical examination shows infrequent blinking and diminished facial expression. Cogwheel rigidity is seen at both wrists. He walks with short, shuffling steps. Mental status examination shows no abnormalities. Which of the following is the next best step in pharmacotherapy?
Add carbidopa-levodopa to the current regimen
Add ropinerole to the current regimen
Add selegiline to the current regimen
Discontinue alendronate
Discontinue metformin
Discontinue metoclopramide
Discontinue verapamil
