<qa>  What is the mainstay of treatment for patients with Parkinsons disease?Medical therapy is the mainstay of treatment for patients with Parkinsons disease PD. After several years of drug therapy, however, a large proportion of patients experience worsening of their parkinsonism and develop incapacitating motor fluctuations and dyskinesias. To deal with this, attention has been directed to surgical procedures, such as deep brain stimulation DBS. Recently, stimulating the areas of the brain that control movement, the globus pallidus Gpi and subthalamic nucleus STN, has been proposed as a therapy for treating many of the disabling symptoms associated with PD and drug-induced side effects. 