My personal experience with CR and S100 is that they quite different in response times and duration .In my opinion they are not going to give the same response. I think that some neuros believe that CR is newer and a direct replacement for S100. I take both of them but by itself CR gives me almost no response, it is like background music and it only helps to smooth the peaks and valleys of S100 I take S100 every 2 1/2 hours 3 times a day and CR twice a day 5 hours apart. You might want to check the web site for SInemet . I also had the DBS and was able to cut my meds by 40% and increase the interval from 1,5 hours to 2,5 ----- Original Message ----- From: Ervin McCarthy To: [log in to unmask] Sent: Sunday, January 23, 2000 02:44 Subject: Sinemet A question about Sinemet. The doctor gave me a prescription for 50/200CR four times a day. If I use up the remainder of my Sinemet 25/100CR two pills to equal the 50/200 C. R will that have the same effect? it may seem like a dumb question but I have a lot of 25/100CR left. Thanks for any information.