My dad has Parkinsons Disease, and when first diagnosed his neurologist had him on Sinemet. He did really well with it for a few months, then he started hallucinating beyond control. We had him admitted to the Senior Care center at the hospital where a psychiatrist saw him and diagnosed him with Lewy Body Disease, saying that the drugs he takes for PD can bring out the effects of PD when it is actually Lewy Body Dementia and
not PD. Does that make sense? But his neurologist still says it is PD, and I just don't know anymore. I am just trying to make him comfortable.
Good luck with your grandmom!