I hope that I did not precipitate an ill-considered aversion to Aspartame
with an earlier posting. I was just reporting my personal experience.
 
What happend was that the tap  water in the town where I live is not very
palatable (the odd dead crocodile in the local river may give it added body
but the use of Alum in precipitating the sediment may give it a metallic
flavour :-). To make the tap water taste better I had been adding a sweet
blackcurrant syrup. At first I did not make the connecion but the
sweetening in the syrup was aspartame and I often drank it when I took my
levodopa at 4 hour intervals during the waking day (I also take eldepryl
twice a day). The levodopa was somewhat erratic in its effect. I read the
label on the syrup bottle and noted that aspartame includes phenylalanine
which has a molecular structure not unlike levodopa. I can't remember the
source but someone else has pointed out that the transport of levodopa into
the brain is a bit difficult as there is competition amongst several
molecules for the transport mechanism. If phenylalanine from aspartame
competes against levodopa then the effectivness of the levodopa could be
diminished.
 
I substituted cane-sugar sweetened blackcurrant syrup for the aspartame
sweetened syrup and the levodopa became much more predictable. To double
check I went back to the aspartame syrup  and my PD symptoms (mostly stiff,
slow and sore - little or no tremor but constipation, fatigue, lack of
concentration,  blackouts and lightheadedness etc. etc.) either remained
longer or re-emerged after an hour or two. Back to the cane sugar variety
and I was almost entirely symptom free for four hours per capsule. I
repeated the cycle of switching betwen sugar and aspartame a couple of
times and became personally convinced that the aspartame did inhibit the
effectiveness of my levodopa. This was not a double blind test - I always
knew whether I was drinking the sugar or the aspartame sweetened variety.
 
After some months and with some other changes in my diet and life-style
(and further medication - florinef, to counter my low blood pressure) I am
free of all PD symptoms for most of the day.  A significant dietary change
was substituting crushed linseed for oat bran at breakfast (I add it to my
regular cereal). I no longer regard constipation as a serious problem.
 
I would like to encourage other Parkies who find their response to
medication somewhat erratic to discuss dietary changes, more exercise, and
reducing stress, with their doctor. It worked for me and may work for them.
 
Best wishes to everyone
 
 
 
Andrew Wake
Faculty of Education,
Central Queensland University
Rockhampton
Queensland
Australia 4702
Phone (079) 309694
Fax    (079) 309604
e-mail [log in to unmask]