The challenge of non-motor symptoms in Parkinson's disease.

The non-motor symptoms (NMS) of Parkinson's disease (PD) are often poorly recognized and inadequately treated in contrast to motor symptoms and a modern holistic approach to treatment of PD should, therefore, include recognition and assessment of NMS. Certain aspects of the NMS complex of PD can be improved with currently available treatments, both dopaminergic and non-dopaminergic, but other features may be more refractory illustrating the importance of research into more effective drug therapies for the future. The American Academy of Neurology has recently published the first task force guidelines in relation to treatment of NMS of PD.