Hi, bonnie - As others have written, Mirapex is a dopamine agonist. It should help make more dopa-mine available to the brain without having to add more Sinemet, which can cause side effects. I'd be interested in knowing if your dad noticed any difference in his symptoms after adding the Mirapex. If a PWP (person with Parkinson's) is adequately medicated on Sinemet, then the addition of Mirapex could cause over-medication type side effects unless the Sinemet is reduced. If your dad is still walking slowly and in fact hasn't seen any improvement since the addition of the Mirapex, it would make me wonder if he's still undermedicated. It's not uncommon to not experience "on" and "off" times in the first few years of PD, btw. Margie Swindler cg for Dick 54/17 << The new med that my dad is taking is Pramidexole / Mirapex in addition to Sinemet. What does Mirapex do different from the Sinemet? Dad says that he doesn't have on/off's or at least there is very little difference between the two. Is that aanyone esle's experience? He continues to have slow, awkard walking, after he gets started, etc.