Dear Rick, Mirapex is an Agonist which serves to improve the functioning of the levodopa ( Sinamet) in the brain. Just about all the other Parkinsons medications one hears about, e.g., Permax, Parlodel, Mirapex, Requip, and Tasmar are Agonists. If you have a fax number available and would like to have additional information on this subject, I could fax some recent publications. [log in to unmask] ( Jack Dempsey)