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Hello everyone. Here I go with the second installment of my comments, which
were prompted by the request for help from Brenda Challingsworth.

Hello Brenda.  It would appear that you are one of those unlucky people who
suffer an adverse reaction to Levodopa. You can take some comfort from the
fact that most of the PWPs who experience nausea find that by going back to
the beginning and 'creeping up' on the problem, they are able to condition
themselves to tolerate the Sinemet (Or Madopar). Incidentally, because
Madopar is for some reason not available in the USA, Sinemet is the only
branded make of tablet available, and the name Sinemet is used
interchangeably with Levodopa, rather as Hoover is used to denote vaccuum
cleaners. For the purposes of this note, if I write Sinemet, you can use
Madopar if that is what you have been given.

You may be advised to take your tablet with meals to offset the nausea,
which it might well do.  However, this works because the protein in the
food competes with the levodopa for absorbtion via the lower intestine,
thus prolonging the exposure of the levodopa to the efforts of the many
bodies whose job it is to break down the many large neutral amino-acids, of
which Dopamine is one. In effect, your nausea is reduced because the
quantity of Levodopa reaching the brain is reduced.
You will see (I hope) that buffering Sinemet with food is rather pointless-
you can get the same effect with more precision by reducing the dose size.

Practical suggestions:
 1) Forget for the time being the dosage rate suggested by your Neurologist
 and try to break up whatever tablet you have been given so that each
 portion contains about 10 mg of levodopa. If you have been given the
 tablets labelled 25/200 (200 mg of levodopa) this may be difficult. I
 would suggest that you prevail on your Doctor (who I assume is the one who
 actually writes out the prescription) to provide you with tablets of a
 lower denomination (The lowest that I know of is Sinemet 'LS' or Madopar
 '62.5', which both contain 50 mg levodopa per tablet.)

 2) Starting with your lumps of tablet containing 10 to 12 mg of levodopa,
 try taking one per day. The most effectve time to take levodopa and so
 the one most likely to cause nausea is 30 to 60 minutes before a meal, so
 try to work round to that timing.

 3) When you have succeeded with that first portion, try adding another lump
 ,to be taken at a different time of day.

 4) Follow this procedure progressively until you can tolerate whole tablets
 as a single dose, and you have won.  It is worth taking time, and
 persevering with this procedure, because these tablets are going to be an
 increasingly significant item in your life, potentially for many years to
 come.

This brings us to the final of my three subjects: What is a sensible
introductory dose of levodopa? Here I have to resort to my well-used charts
A and B. which I originally published on 18 th Dec 96. I don't want to
impose them again on the entire list, so if there are any newcomers who may
like to see them , if you email me privately I will send them on to you.

I believe that the model which is described in the charts A & B  is
realistic, although very much simplified. Therre is little point in
repeating here what is written in the text accompanying the charts; suffice
to say that it shows that all that is needed by a person just starting PD
is ideally a tablet which releases a small quantity of levodopa over a long
(4 to 6 hours) period of time. Unfortunately such a tablet does not exist.

I quite often see examples where the Sinemet 50/200 tablet is prescribed
for new PWPs. It is ironic that we are capable of accepting such a large
quantity of levodopa when we have no need for it, and in later years,
when we really could use the levodopa, we are unable to accept it because
of the dyskinesias which would result. The large potential overdose implied
by the 200 mg tablet is offset by the brain's control system which shuts
down enough of its remaining dopamine production capacity to preserve the
required overall dopamine rate.

We thus have two ways in which we can live with PD in its early stages:
  1)  Take a large (200mg) tablet at infrequent intervals. The big
  advantage of this is obvious - you can pop three or four tablets a day,
  at intervals of 5 or 6 hours, and get on with the business of living.

  2) Simulate the non-exsistant small scale controlled release tablet by
  taking say half a Sinemet LS tablet, every 2 or 3 hours through the day.

It is easy to see which option would be more popular, and I know of no
reason why option 1 should not be followed. Ultimately, as the PD
progresses, the two options converge, and effectively become one, at which
point things start to get a bit tricky, but that is several years into
the future for today's new starters.

I hope that some of what I have written here will help you newcomers to
gain some understanding of the processes involved in PD. It is
complex, but we are talking about the rest of our lives here - It deserves
some effort, don't you think?

Regards to you all, and a Happy New Year.
--
Brian Collins  <[log in to unmask]>