Shortly after dx in 1995, I was started on Artane. It shut the tremor down immediately, but I had serious vision problems. Since I was still working and had a long cmmute the Artane had to go. Has your husband tried Amantadine? I believe it has some anticholenergic properties. i have been taking it for many years and it really helps me along with Sinemet, Selegeline and Mirapex. Good luck!
MK2