Update on the diagnosis and management of Parkinson's disease.

Parkinson's disease (PD) is diagnosed where bradykinesia occurs together with rigidity or tremor, in the presence of supporting features. The diagnosis is clinical, and attention should be paid to exclusion criteria indicating an alternative diagnosis and to 'red flag' features. There is no cure or disease-modifying treatment for PD, and the rate of progression is variable. The most effective symptomatic treatment remains levodopa, which has superior benefits for quality of life in early PD compared to other therapies. Motor fluctuations and dyskinesia later in the disease course can be improved with adjunctive treatments. Around 10% of patients per year with refractory motor fluctuations may be eligible for advanced therapies, including deep-brain stimulation surgery. There is emerging evidence for the management of non-motor symptoms in PD, and the importance of multidisciplinary care. In this article, the evidence base for optimal diagnosis and management of PD is discussed.