Hi, Pam Here, I have been taking Permax for some times now and find it excellent. I do get the occasional involuntary movements that drive me crazy but on a whole it is very good. It does lengthen the duration period of the Sinemet. Occasionally I do feel a bit dizzy but not alot. I am also taking a drug called Proponolol I think that is how you spell it. That is very good I take it three times a day with my meals because it can make you a little stomachy. My tremor is very much controlled with this. They perscribe this drug for people with high blood pressure. Hope this is of some help to you. Over a period of time your system will become used to the drug like anything else. I was told it could cause hallucinations but I haven't experienced this. Regards Good Luck. Pam, 43,13.