If more than your hand/arm is shaking, it may be a type of seizure. Have you had that checked out and have you seen a neurologist? Some tremors in the hands are considered "benign" and you don't have to be concerned about them if you get them cleared by your doctor. My neurologist said he will prescribe me medication for mine if they get to the point I can't stand it or they cause too many problems. I take enough medication as it is so I have been delaying it.