Snapshot A 58-year-old man is brought by his wife due to worsening weakness and fatigue. She describes his movements as "sluggish." The patient reports difficulting with typing on his keyboard and buttoning up his pants. On physical exam, there is a "pill-rolling" tremor at rest that improves with purposeful movement. There is also increased resistance to passive movement at the wrist and elbow. He is started on levodopa and carbidopa. Introduction ↑ L-DOPA catecholamine precursor medications levodopa/carbidopa login to view 13 more bullets Dopamine receptor agonists bromocriptine (ergot alkaloid) pramipexole and ropinirole (non-ergot) ↑ Dopamine availability amantadine an antiviral medication that can improve parkinsonism login to view 3 more bullets toxicity login to view 2 more bullets Preventing dopamine metabolism monoamine oxidase type B inhibitors prevents the degradation of dopamine into 3,4-dihydroxyphenylacetic acid (DOPAC) medications login to view 2 more bullets catechol-O-methyltransferase (COMT) inhibitors prevents the degradation of dopamine into 3-O-methyldopa (3-OMD) medications login to view 2 more bullets Anticholinergics under normal conditions, dopamine and acetylcholine are in electrochemical balance in the basal ganglia ↓ dopamine in Parkinson's disease (PD) leads to ↑ cholinergic sensitivity login to view 1 more bullet medications benztropine trihexyphenidyl