I'm glad this topic has been brought up, as I too have very much wanted an explanation of this phenomenon. I experienced this before my PD diagnosis, when I described it to my neuro (who was treating me for migraines & insomnia) as an "internal revving motor..........at that time I was taking a low dose of Sinequon with Xanax......then the Xanax was replaced with Buspar (needless to say, my "anxiety" didn't improve). At that same time, I was experiencing hot flashes, etc. because of menopausal hormonal fluctuations, which may or may not be relevant. When I then received the pd dx, I was started on Sinemet, Paxil, & Trazadone (for sleep). No further problems with internal shakiness until several months ago. At the time I was taking estrogen & progesterone, & having severe daily migraines. Also, the internal revving was happening again, & a difficulty which I don't remember having before - the need to breathe deliberately & deeply. After some ado, I discontinued the hormones ~6 wks ago. The migraines have shown moderate improvement, but the other symptoms remain. I'm hoping that soon whatever confounding effects the hormones have contributed will be out of the picture. It will make things much easier if whatever symptoms remain can clearly be tied to the pd. Perhaps one or more of our list members can at least explain the internal shakiness, for my benefit & for the others who experience this. Explanations of the other issues I mentioned are also most welcome! Mary Legan 55/5+ <My mother Joyce (68/6 months) changed doctors recently. She was taking 25/100 Sinemet 4.5x/day, .25 Permax 5x/day, 10 mg. Paxil 1x/day. Her new doctor wanted to reduce the Sinemet a bit and start her on Eldepryl. This required her getting off the Paxil. About 4 days ago, she stopped the Paxil and started feeling shaky inside -- a nervousness that wouldn't quit. She decided today to continue the Paxil again (she hadn't started the Eldepryl) and felt better. She suspects this internal shakiness/nervousness is a side effect of the Permax. Any thoughts on this? Has anyone had a similar sensation? Was it related to a particular drug. Thanks. Debbie White [log in to unmask]