I’ve attached an excellent article that explains a little bit about non-motor symptom. It includes a runny nose, but does not say anything about congestion. I they couldn’t find anything that specifically mentioned congestion.

I did find an article that discussed the pitfalls of taking Anticholinergetics, like Benadryl, that may be taken to treat congestion. They include memory loss and dementia, so I included that t as well

https://www.apdaparkinson.org/article/uncommon-....

https://www.parkinson.org/blog/research/anticho....