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On Tue 25 Feb, Ida Kamphuis wrote: > Dennis whrote > > 1. the exponential decay rate is operative on all deliveries of the drug, once they are in the blood stream. 2. this in turn will result in a small, but significant increase in the drug levels over the delivery period of the tablet, culminating in a peak at the end of the dose. > Ernie wrote > Dennis, it could indeed explain it. Whether a particular individual would suffer this effect would also be complicated by the exact Levadopa peak required to trigger the dyskinesia, > > Dennis and Ernie and others, > > The story of the manifacturer about exponential decrease of a part of the sinemet is very concordant with my reactions. However about the wearing off dykinesia for me things are the other way round. The worst wearing off dyskinesia is for me the one which comes 3 or 31\2 hours after taking the first > >Hello Ida, Ernie, Dennis and others : I did say that I would not comment any further, until I had some traces from you to look at, but why should I miss all the fun to be had, speculating in a vacuum? I just want to register a couple of points: 1 I don't trust the statement that the CR tablet decays exponentially as it comes to the end of its effective life. I seem to recall seeing actual measurements (I think Ron Vetter has them on his web pages) . That should clear some of the smoke away. 2. Don't forget that the blood plasma levels, which are the nearest that they can get to take measurements of what is happening, are still some way from tthe brain itself. In particular, there is the blood-brain barrier, I have my own theory about how this affects the levodopa (and I have seen papers which say similar things), and that barrier makes a significant change to the shape of the graph that really matters i.e. what really reaches the important place, which is the brain itself. In my view, the nearest that we will ever get to that is my condition plot (+2 to -2). The trick to avoiding endless speculation about intermediate stages is simply to jump right over them. Don't you agree? Regards, -- Brian Collins <[log in to unmask]> ------------------------------------------------------------------------------ --------------- There are many conjectures out there, but is there a pharmacokinetic analysis of the reaction to determine whether it is a first or second order. That would determine the slope of degradation.; or are we whistling in the wind? MM