This is an article for these issues in advanced PD. However, PWP’s have symptoms at various times in the course of the disease, and I found this article to be relevant at any stage.

https://www.apdaparkinson.org/article/bowel-and...

I need more fiber in my diet.

I don’t know either but I’m the opposite of constipation and get the urge to empty my bladder and it’s barely need to go, to having to now or else! Hopefully someone knows the answer.