Parkinson's with Stage 4 Prostate Cancer

@safari1949 that is a very specific question that perhaps only your oncologist in collaboration with your neurologist can answer. I have added this message to the Parkinson's group as well in case someone there has experience with both conditions. (https://connect.mayoclinic.org/group/parkinsons-disease/)
You could also talk to your pharmacist about this. They know so much about drug interactions.

Is your oncologist aware of your Parkinson's? Do you take any medication for Parkinson's?

Yes my oncologist has talked to my neurologist. I only take Rasagiline for the pD. I will definitely talk to my pharmacist tomorrow. My wife and I had talked about that earlier today.

I'd be interested to hear what you find out if you don't mind posting it.

According to our pharmacist there is no problem interaction between the Zytiga and the Azilect (Rasagiline). Good to know.

Hi @safari1949, I'm so glad that you checked with your pharmacist. It is reassuring to know that there are no interaction issues with the drugs you're on for 2 different conditions. Pharmacists are a wealth of knowledge and readily available to answer such questions as part of your health care team.

I also was curious and asked your question to a pharmacist here at Mayo Clinic. She offered this additional information.
"Corticosteroids provide effective treatment for such a diverse array of conditions. As you know side effects depend on the dose, duration and route and of course vary by individual as well. Over a long steroid course patients could see high blood sugar, osteoporosis, infections and slowed wound healing.

Some information suggests that medications that suppress the immune system like prednisone may actually protect against Parkinson’s disease but more study is needed. See this article by Washington University School of Medicine
- Drugs that suppress immune system may protect against Parkinson’s https://medicine.wustl.edu/news/drugs-that-suppress-immune-system-may-protect-against-parkinsons/