Welcome to Connect, @patpambern. Having itchy skin seems to be pretty common with Polycythemia Vera. There are a few members in the forum going through the same thing with their PV and share their experiences about how to quell those itches!
Here’s one of the discussions that might be helpful:

PV itching, not after bathing!
https://connect.mayoclinic.org/discussion/pv-itching-not-after-bathing/
How long ago were you diagnosed with PV? Are you on any treatment plan for this such as phlebotomies or taking hydroxyurea?

Hello @patpambern, I have PV and have had spontaneous itching when newly diagnosed. I now take Zyrtec and Pepcid once a day and have not had itching in a year. I still avoid hot showers as I am afraid to test the theory but I no longer have itching. I read the article attached below and that is why I chose to take these over the counter meds. Good luck. I know the relentless itching is life altering. I hope this information helps you.
Best,
Andrea
https://www.pvreporter.com/otc-combo-zyrtec-zantac-helping-polycythemia-vera-patients-get-relief-itching/