Motor complications in Parkinson's disease.

Management of motor complications in advanced Parkinson's disease (PD) can be challenging. The main complications are inadequate dopaminergic tone ("off" time and dose failures) and excess dopaminergic tone (dyskinesia). These motor complications increase as PD progresses. Changing the dose and timing of L-dopa is the main strategy for both scenarios. Reducing "off" time can also be achieved by the addition of adjunctive therapies (dopamine agonists, catechol-O-methyl transferase inhibitors, and monoamine oxidase-B inhibitors). Dyskinesia can improve with amantadine and possibly several other medications. Surgical interventions such as lesioning and deep brain stimulation are considered when pharmacological strategies for motor complications are not satisfactory.