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Ron Vetter asked me on the email about the use of patches for delivery of levodopa. I told him there are considerable technical difficulties associated with this method of delivering levodopa as well as carbidopa. Levodopa is only stable for more than a few short hours when it is maintained as a solid but solids are known to work in some patches. Carbidopa or a substitute has to be adminstered along with the levodopa to prevent absolutley terrible side effects. Patches are not yet advanced enough technologically to deliver more than one drug. So two patches would be needed. Then there is the problem of dose. Most patches can only deliver several miligrams of drug per day. Unfortunately most people on levodopa need at least 300 mg per day plus at least 75 mg of carbidopa. These doses are just too much for present patch delivery systmes to handle. The only hope for a levodopa patch would come if a patch manufacturer made experimental patches and then showed not as much levodopa is needed to achieve efficacy. This is a difficult task because it will have to be done with many many patients and for varied lengths of time in order to convince the FDA that the drug works in that format. Ron also asked if there were many companies making patches for use with any type of drug. The answer to that is no. I know of two for sure (Cygnus and Theratech) and there could be a third - possibly Elan. There are other companies selling drugs in the patch configuration but they are manufactured for those companies by one of the above. I think your best bet for the moment is keep using the solid tablets, but that does not mean you and I should not seek better means of therapy. Best regards, Joe Irr