haven't tried it. saw my neuro last week and he said he has one advanced pd'er that was doing better on it but he didn't suggest i try it. i was diagnosed 13 years ago so i would be a candidate. food/protein/gastric emptying affects rytary just like C/L, i would think even more since it's CR and if it passes quickly thru your stomach into the small intestine it may have no affect, i could be wrong about that though.
here's a thread on rytary.
http://forum.parkinson.org/index.php...les/?hl=rytary
you need to read thru the 3 pages, paints a picture of a drug that may take some time for neuros/patients to figure out dosing and if your're working you might have down time. so you definately want to start trying it on day's off, you can always go back to regular C/L.

here's another site
http://www.parkinson.org/NationalPar...2ed3d4ab34.pdf
How to Dose Rytary (Carbidopa and Levodopa extended release