I just had cortisone shots in both shoulders for and a one quick shot in my neck muscle for Rheumatoid Arthritis joint issues. My left back muscle under my shoulder blade spasmed about 10 minutes after the shots and proceeded to affect my lung from breathing. It is 8 hours later and I still have issues with my lung breathing - I hope I can sleep. It feels like I have a pulled muscle in the middle of my chest. Also I just got a cramp in my foot. After taking 1 mg Prednisone daily...and shots every 3 months for the last few year - I have never experience muscle cramps. I have had some heady feelings - but that far outweighs the amazing pain relief from the shots. I would like to find another answer to help my pain than any type of cortisone. I am 37 yr old healthy slim woman (other than arthritis).