Hi Brian, I forwarded your message on to Hein, and will let you know what he says, if any lay person would know the answer, it will be Hein. However, maybe some of our Doctors or Pharmacists could answer you professionally. What I don't understand is why it has to be re-registered. Years ago when I was having hot flashes, the U.S. Air Force Doctors gave me Bellergal, which worked wonderfully and didn't have any hormones in it. Actually Bellergal, if I remember correctly was for morning sickness, but it sure worked for hot flashes. I couldn't take a hormone replacement as I had, at one time, blood clots in my legs, and they wouldn't take a chance giving me hormones. I had a woman Doctor,and she was up front with the fact that it wasn't for hot flashes, but it had been used for it very successfully. She was 100% correct, I never had hot flashes while I was taking it, and I never developed anymore blood clots. Right now I'm so happy and satisfied with Sinemet I wouldn't want to change, but maybe later, one never knows! As Ever, Marjorie Moorefield just another librarian with PD P.S. several months ago I asked about "dropped foot" problems with PD, and all of you gave me good advice, which I should have followed sooner. The brace for my foot is ready and I'll get it on Thursday, however, I waited too long, and now I have trouble with my knee, which could have been avoided, if I had taken the time to go to the Doctor earlier . Please take a fools advice, if it hurts, go to the Doctor promptly!!