 |
 |
Brian... for optimum accuracy, your statement: "Don't forget- just because you could get away with it last year, doesn't guarantee that you can do the same this year." SHOULD read, "Don't forget - just because you could get away with it YESTERDAY, doesn't mean you can do the same TODAY." (speaking from my own personal experience with PD, of course) <rueful grin> Barb Mallut [log in to unmask] ---------- From: Parkinson's Information Exchange on behalf of Brian Collins Sent: Sunday, February 22, 1998 6:28 PM To: Multiple recipients of list PARKINSN Subject: Re: CARBIDOPA poisoning?10/10 or 25/100? On Sun 22 Feb, Ivan M Suzman wrote: > ^^^^^^WARM GREETINGS FROM^^^^^^^^^^ > Ivan Suzman 48/10 [log in to unmask] > Portland, Maine land of lighthouses 40 deg. Fmelting snow > *********************************************************** > Dear Brian, Stefan, Dennis, Ron, Linda and Gail, > > Linda Corson asks: "... my basic nuts-n-bolts questions are: > > 1. What's the minimum daily carbidopa level for the levodopa to be > maximally > effective? > 2. What are the side-effects of too much carbidopa? > 3. At what level do the side-effects typically start to app ear?" > > I also would like to add another question to the fascinating > carbidopa/levodopa discussion occurring on the list. My "kick-in" time > for Carbidopa/levodopa 25/100 is about 35 minutes, with some variations. > > QUESTION: Would a 10/100 pill kick in at the same rate? > > I am wondering how the c-dopa/l-dopa ratios (1/4 and 1/10) influence a > PWP's dosing schedule. > Ivan Hello Ivan - Here are my answers- They may differ a little relative to Stefan's because we have somewhat different interpretations. 1) 75 mg/day seems to be a widely-accepted figure. 2) Side effects are not very specific, but include tiredness, lack of energy, and nausea. 3) There appears to be quite a wide gap in intake before the symptoms really show up: I have positively identified only 2 people with Carbidopa poisoning, ( by which I mean that their symptoms went away when the carbidopa level was reduces) - and both those people were taking in excess of 400 mg Carbidopa per day ! I would say that you should aim to keep below 300 mg if at all possible; it's not critical in my experience. Aha my favourite hobby horse: Kick-in of tablets. To answer your question, since people are usually talking about the first tablet of the day when they use the 'kick-in' term, I would not advise a 10/100 tab: The Carbidopa will not have built-up to the optimum level, and you may lose some of your levodopa. Another thing to remember about Kick-in effects: if I feel a 'kick-in ' effect (That is, a sharply-defined transition from under -dosed to On condition, I know that I have blown it! The way that a tablet dumps its cargo of levodopa looks like an 'S' shape: A rounded start; a fairly constant and steep rise in concentration , followed by a rounding- off at The peak value, then an exponential drop back to zero. Between the rounding off and the decay there may be a flat area where every thing is fine: This is the area where the brain is compensating for any excess of levodopa. (see my previous posts on this ) With reference to that rounded-off top level, the transition to the level part of the response curve is only abrupt if you are 'shooting through' to a higher figure than the optimum. Whether or not your brain can tolerate that over dose depends on how many years you have had PD, and where you are positioned in the down-hill path of PD. Don't forget- just because you could get away with it last year, doesn't guarantee that you can do the same this year. Regards, -- Brian Collins <[log in to unmask]>