Quilo, a 47-year-old male, is experiencing muscle stiffness and shaky hands. During an office visit, the physician assistant also notes his stooped posture. Tests identify a deficiency of dopamine, which helps confirm a diagnosis of Parkinson disease. Since there is no cure, Quilo is unhappy and uncertain about taking his prescribed medication (levodopa plus carbidopa or Sinemet). How can you help him understand his condition and explain how his medication will benefit him?