A 53-year-old woman with Parkinson's disease and a moderate tremor with no other signs, what is the most appropriate initial treatment?

• A. Lorazepam (Ativan)
• B. Haloperidol (Haldol)
• C. Ramatidine (Flumadine)
• D. Levodopa/Carbidopa (Sinemet)

Answer: (D)

In Parkinson disease, the most effective way to relieve motor symptoms, including tremor, is to replace brain dopamine deficits. Levodopa is a dopamine precursor that crosses the blood–brain barrier and is converted to dopamine in the CNS; adding carbidopa inhibits peripheral conversion, so more levodopa reaches the brain and side effects like nausea are reduced. This combination provides the strongest and most consistent improvement in tremor, bradykinesia, and rigidity, making it the best initial treatment for a patient with a moderate tremor and no other signs. Other options don’t address the underlying dopaminergic deficit or can worsen Parkinsonian symptoms: lorazepam is a sedative that doesn’t treat the disease itself, haloperidol worsens parkinsonism by blocking dopamine, and rimantadine is an antiviral with no role in PD management.