Parkinson’s disease belongs to a group of conditions called motor system disorders, which are the result of the loss of dopamine-producing brain cells. Parkinson's disease usually affects people over the age of 50. Early symptoms are subtle and occur gradually. In some people the disease progresses more quickly than in others. As the disease progresses, the shaking, or tremor, which affects the majority of patients, may begin to interfere with daily activities. Patients may also experience depression and other emotional changes; difficulty in swallowing, chewing and speaking; urinary problems or constipation; skin problems; and sleep disruptions.

At present, there is no cure for Parkinson's disease, but a variety of medical and surgical treatments can provide dramatic relief from the symptoms.