In Rheumatoid arthritis condition there will be auto immune inflamation in body which will cause pain and swelling with this if the patient does not move his joints there will be more inflammation and there will be more swelling and pain. Which will start damaging the cartilage of the joint and will go for deformity over the period of time. Here the condition called as autoimmune because the immune system of the body which is suppose to fight only against the foreign body will start action ( inflammation ) against body cells. The classical symptom of rheumatoid arthritis is early morning stiffness for all small joints of body, specially for hand and feet. The only treatment is anti inflammatory, and immuno supretion drug therapy along with regular exercises which help to reduce inflammation in body. I also suggest my patient to follow anti inflammatory diet like have good amount of omega 3 to have some more anti inflammatory effect in body. For fibromylgia again here also its a auto immune inflammatory condition but this affects mainly the muscles. Here the cause could be too much stress level on body, or heriditory any thing. And again the treatment is exercises, anti inflammatory drugs, and some more medication like vitamine b complex based in your body need and as directed by your doctor. You can also use cold pack frequently on your painful area for some Some more relief. For detail discussion on drug interaction I suggest talk to your doctor he is right person for you since he has seen you with physical examination and have also seen all your previous as well current reports. Take care