Overview Snapshot A 73-year-old man presents with fatigue. He reports having difficulty with activities of daily living. He states that his wife notes he is not swinging his arms as much as he used to when walking. On physical examination, a tremor is noted at rest, that improves with purposeful movement. He also walks with a stooped posture during gait testing. He is eventually started on levodopa and carbidopa. Introduction ↑ L-DOPA catecholamine precursor medications levodopa/carbidopa login to view 14 more bullets Dopamine receptor agonists bromocriptine (ergot alkaloid) pramipexole and ropinirole (non-ergot) used in the treatment of restless leg syndrome ↑ 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