Autonomic dysfunction.

Autonomic symptoms affect most patients with Parkinson's disease (PD) and often have a profound impact on their prognosis. Symptoms include orthostatic hypotension, gastroparesis, constipation, excessive sweating, and sexual dysfunction, however, these symptoms are frequently unrecognised by clinicians and remain untreated. The mechanism of autonomic dysfunction is attributed to the involvement of the central and peripheral postganglionic nervous system. It is now well established some autonomic symptoms have a diagnostic value because they appear early in the course of PD and may precede the onset of motor symptoms. Early recognition of autonomic symptoms is essential because it will help to expand our knowledge of the nature the neurodegenera- tive process. It is important that physicians both recognize and treat theses complications in an effort to improve quality of life.