T.C.
I have a friend whose arm shook for 14 months straight. Constantly. It was awful. The doctors couldn't figure it out. Her cranial/sacral chiropractor did. There was a nerve in her jawline going from near her ear to her jaw that was pinched. He was able to open it up, and the shaking stopped. I would take her to a sacral/cranial expert if you can find one. Since this happens when she drinks, it makes sense that it could be related. I hope you can find the source of the twitching!