I will be having a PET scan on Monday, and because of the timing of it I will be required to go about 20 hours in between doses of medicine. From 7pm Sunday night to approx. 3pm the next afternoon. I am in my 8th year since diagnosis and have been taking sinemet cr the entire time. This will be the first time I have tried to go without it on a regular basis in all that time. I'm really concerned, I don't know what to expect, but of course fear the worst. Any ideas on how to deal with it? Thanks, Diane