Hi. I have not read all of the responses......but............simply put.....a Dopamine Agonist makes the Dopamine receptors that make Dopamine do what it does best.. work better. An "antagonist" will make the receptor stop doing what it is doing. This works well in the case of something that needs to be stopped. Example? Non PD..........but affects a lot of us. Bladder control is often effected by muscarinic receptors. If that bladder is going crazy (the muscarinic receptors are too active) and one has to go to the bathroom too often or has accidents, a muscarinic receptor ANTAGONIST is in order. I hope this helps. Happy day. Nancy