Managing late complications of Parkinson's disease.

Treatment of parkinsonism becomes more difficult as the disease progresses, and results from increasing neuronal degeneration, side effects from antiparkinsonian medications, or most often, a combination of each. Neurodegenerative parkinson symptoms may result from substantia nigra destruction, or from other areas in the nervous system. These include the cortex (cognitive and psychiatric disorders), brainstem (bulbar abnormalities), intermediolateral cell column (autonomic disturbances), among others. Medication side effects produce motor fluctuations, dyskinesias, delirium, hallucinations, psychosis, orthostatic hypotension, sleep disorders, and a host of other well-recognized complications. This article is divided into sections concerning motor fluctuations, gait difficulty bulbar disturbances, autonomic disturbances, sleep disorders, cognitive disorders, and psychiatric disorders, and is an attempt to provide the reader with strategies for treating common complications in the advanced Parkinson's disease patient.