Hi Joy: I have taken Lithium and depakote in tandem for Bi-Polar Manic Depression. Works great and I've taken it for 10 years. When the thought of PD came up my Psy to rule out the meds took me off both and put me on another med to see what would happen. I shook like normal, I was on inderal, amantadine, I can't remember all the meds but none stopped the tremors, so I went back on Lithium and Depkote. This did not treat or stop anything about the PD. So, I'll just stay with what I have as it works for me. I've had a manic episode , and a depressive episode about 2-3 months ago. With the introduction of PD meds. I must say that in my opinion for me "Cogentin" was the worst med I've had. I had no clue as to where, what, when, time, places it was horrible. Just my input TTFN Gina