Hello, I found this thread while looking up info on the amino therapy program. My husband had been using the program for depression/anxiety NOT Parkinson's, but it's the same program, just modified a bit. He was seeing some changes by the third month but just couldn't take the nausea from the l-cysteine anymore and so stopped. This has been the only thing that has ever helped and so I've been trying to find a way to deal with the nausea. The doctor we were dealing with didn't have any suggestions except "it will pass" or to come up more slowly, which didn't work either. Have any of you on the program dealt with nausea and how did you resolve it? Thanks!