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This is in respomse to the interesting post from Stephan Schwartz, including quotes from Dennis Greene. Dennis' comments refer to my model of how the brain responds to levodopa. This model started off life as a series of observations and facts gleaned in discussions with a neurologist friend of mine. About a year ago, it hardened up into the form of my 'model'. The thing that gives me encouragement is that since then as new discoveries have popped up, and I find that the model can explain these new items without modification. (A good test of a model, I think). My 'Chart A' (available at all good web sites) came out of the model. My reason for writing is that I can settle your concern about Apomorphine and dyskinesia, Dennis. The key point as I see it is that the events which lead to dyskinesia occur ONLY kn the brain of a PWP. In a normal person, only enough dopamine is released to satisfy the requirements of the brain. There is no excess, and so no dyskinesias. In fact, if you follow it through to the end, I believe that if some ingenious person managed to smuggle dopamine across the blood/brain barrier, and even if it was dopamine previously extracted from that same person, a larger-than necessary dose would STILL produce dyskinesias. Just to ram the point home, I am saying that dyskinesia can be caused by an excess of Dopamine, Levodopa, Apomorphine, and if you could absorb enough, probably a certain amount of the well-known agonists like Permax would produce dyskinesias. This is my answer to those doctors who still cling to a half-baked idea (because someone once told them ), that if you use levodopa too early in the progress of the disease, it will 'lose its effectiveness'. I think that is wrong, and that the difficulty results from the continued degradation of the Substantia Nigra which makes it necessary to administer the levodopa, etc more precisely. I have not used Apomorphine myself, (It's on my 'rainy day' list), but I do know people who take it. I think it has the following good and bad points: 1/ It is administered subcutaneously and thus by-passes the entire digestive system, allowing for more precision in administration. 2/ Apomorphine can be taken in such quantity that it can even cause dyskinesias. 3/ A growing number of people in the UK are going for the continuous injection system. It is quite expensive, but the degree of control is good, and you are less likely to end up looking like a pin-cushion. I hope this is of some interest. Regards, -- Brian Collins <[log in to unmask]>