A 73-year-old woman with Parkinson disease comes to the physician with worsening stiffness, shuffling gait, and unsteadiness despite taking the maximum dose of levodopa/carbidopa combination medication. Neurologic examination shows a rigidity of the upper extremities. Her gait is slow, with shortened stride length. Entacapone is added to her medication regimen. This drug most likely improves this patient's symptoms by which of the following mechanisms?

Question

Quizplus · Accepted Answer

Eductional Objective: Parkinson disease is typically treated with levodopa (immediate precursor of dopamine), which crosses the blood-brain barrier.  Levodopa is administered with DOPA decarboxylase inhibitors (eg, carbidopa) and sometimes catechol-O-methyltransferase inhibitors (eg, entacapone) to reduce the peripheral metabolism of levodopa, resulting in increased levodopa bioavailability to the brain

A 73-Year-Old Woman with Parkinson Disease Comes to the Physician