And Drs don't know everything...
So many variables of PD and people respond to meds differently too.
6 friends/relatives of my parents generation (approx age 80s+) all have had different variations..
Sometimes a med change can be tested or if other meds are in the mix, and they aren't working as they should..
We stopped the lesser meds as time passed, as dad was having more side effects & no benefit from them.. Ok per dr.