I am also suffering from Fibro/RA & although I have not tried CBD isolate, i smoke cannabis for my symptoms & it helps but not enough at medicinal doses. Gotta get really baked to get acceptable relief, not good cause it makes me not want to do anything but sit around. I was an all day everyday stoner for 25+ years but when my fibromyalgia symptoms came about, it sapped me of my energy so being stoned all day was no longer an option.
I found kratom leaf & it was the answer to my prayers! It helps me feel normal & gives me the energy to be active for a good portion of the day. Unfortunately, I think it is banned in the U.K. & the dirty bastards at the DEA here in the land of the "free" tried to do a slick ban from under our noses. But the people stood up & let their voices be heard & the DEA tucked its tail & lifted the ban, for now.
There are some powders that bodybuilders use that help (check out the fibro forums) but unfortunately nothing works as well as kratom
Good luck to you mate, I know the hell of living with fibro & RA, can't imagine adding Parkinson's to that mix. Please keep us updated on your search for relief. I might be trying out some CBD vapes in the near future, pretty broke right no lol but I'll definitely pop back on this thread to share my results.
If anyone can recommend effective & affordable CBD liquid that can be ordered online please share. I'm in CA but don't really want to pay for a cannabis rec unless I have to.