Chapter 78: Parkinson Disease

KEY CONCEPTS

• To optimize long-term therapeutic outcomes, minimize adverse effects, and improve quality of life for individuals with idiopathic Parkinson disease (PD), clinicians need to (1) continually access motor and nonmotor symptoms, (2) thoughtfully consider initial and adjunctive therapies, and (3) continually adjust medication dosages throughout the course of this illness.

• In general, treatment should be initiated when the disease begins to interfere with activities of daily living, employment, or quality of life.

• Surgery is an option for patients who require additional symptomatic relief or control of motor complications.

• Anticholinergic medication can be useful for mild symptoms of PD but, due to adverse medication effects, it should be used with caution in older patients and those with pre-existing cognitive difficulties.

• Monotherapy with amantadine or the irreversible monoamine oxidase type B (MAO-B) inhibitors provide symptomatic benefit, but less than that of dopamine agonists or carbidopa/levodopa (L-dopa).

• Carbidopa/L-dopa is the most effective medication for symptomatic treatment.

• Most patients treated with carbidopa/L-dopa will develop motor complications (eg, fluctuations and dyskinesias).

• MAO-B inhibitors (irreversible and reversible), catechol-O-methyltransferase (COMT) inhibitors, and adenosine A2 receptor antagonists are useful add-on therapies to attenuate motor fluctuations in patients treated with carbidopa/L-dopa.

• Amantadine is a useful add-on agent to attenuate dyskinesias.

• Dopamine agonists are effective and, compared to L-dopa, associated with less risk of developing motor complications. They do, however, carry a greater risk for psychiatric symptoms, such as hallucinations and impulse control disorders.

BEYOND THE BOOK

Refer to Chapter 69: Parkinson Disease: Slow and Shaky Level III in Pharmacotherapy Casebook: A Patient-Focused Approach and read the initial patient presentation to answer the following questions.

(1) What medications may be considered for treatment of this patient’s uncontrolled PD? List the different medication options along with specific treatment considerations for this particular patient such as adverse effects, tolerability concerns, etc.

(2) This patient shares that they just saw a commercial for a new medication for Parkinson disease, opicapone, and wants to know if this would be an option right now. Explain why opicapone would not be an initial medication choice for this patient.

(3) Upon closer evaluation of the patient case, you notice that there is no history of past medications this patient has used. You would like to get this information to assess for medication-induced parkinsonism. Create a list of medications that can cause parkinsonian symptoms, and the mechanism by which they can induce symptoms.