I would suggest investigating some version of the paleo diet. One version of the diet used to help people with auto-immunity is that taught by Dr. Terry Wahls. Rheumatoid arthritis, I believe is often caused by vaccines. Pharmaceuticals may suppress this, but not cure it. I do not know if quinine is safe for someone with RA, but a good source of quinine is tonic water. HCQ,if you don't know, is the pharmaceutical derived from quinine. I use Q tonic.
https://terrywahls.com/about-the-wahls-protocol/