A Nursing Student Asks the Nurse Why Patients Who Have

A nursing student asks the nurse why patients who have parkinsonism receive a combination of carbidopa and levodopa. The nurse will explain that the combination product:

A) allows larger doses of levodopa to be given without causing increased adverse reactions.
B) causes more levodopa to be converted to dopamine before crossing the blood-brain barrier.
C) eliminates almost all drug side effects of both levodopa and carbidopa.
D) reduces peripheral side effects by inhibiting dopa decarboxylase in the peripheral nervous system.