Steph,
I had a period where my right jaw, lips, eye, and neck muscels would tremor. I know the cramped feeling around the mouth your talking about. As it turned out I was getting too much Sinemet. My MDS cut back the amount of Sinemet I was taking and these problems went away. As we are all different, talk to your doctor. It may be too much Sinemet or maybe a timing issue.

GregD