Managing motor complications as Parkinson disease progresses

Most patients with Parkinson disease on levodopa therapy eventually develop motor complications. These include:

• different patterns of motor fluctuations (eg predictable and unpredictable ‘wearing off’ of effect, intermittent ‘dose failures’, delayed or poor effect of individual doses)
• drug-induced chorea (also known as dyskinesia) or dystonia.

Patients with Parkinson disease who are especially at risk of motor complications:

• are younger at onset
• have more severe disease
• are on a higher levodopa dosage
• have had the disease longer.

Smaller, more frequent, evenly spaced doses of levodopa are often needed to manage motor complications. High-protein meals may interfere with levodopa absorption, so modifying the diet and avoiding dosing at mealtimes (eg giving drugs 1 hour before meals) can be helpful. Adherence to regular dosing times is important, as variations from the patient's usual schedule can lead to deterioration in function.

Refer for expert advice to manage motor complications of advancing Parkinson disease. Combination therapy is often needed, and adjusting drug therapy is complex.

To manage ‘wearing off’ of therapy, an expert may choose to:

• combine levodopa and a dopamine agonist
• use modified-release levodopa
• give smaller, more frequent doses of levodopa
• adjust dietary protein
• switch dopamine agonists
• use a catechol-O-methyl transferase (COMT) inhibitor (ie entacapone)
• use rasagiline or selegiline.

To manage dyskinesia, an expert may choose to:

• decrease the levodopa dose
• add amantadine
• add a dopamine agonist or increase its dose
• switch dopamine agonists.