Are the pains from a joint, muscle, or something else? Are they radiating pains or point pains? Joint pains are a common extra-intestinal complaint of uc patients, as we can get various types of arthritis (joint inflammation, also autoimmune).
www.ccfa.org/assets/pdfs/arthritiscomplications.pdfWe can get pains from our intestine, mostly just when flaring badly. We can also get pains from our kidneys, get pancreatitis, get gallstones, have uterine cysts, and other sources within our abdomen where many organs are closely packed. It's important to know exactly what is causing the pain as some of those (like pancreatitis) require treatment. If there's any question about
the source of the pains then I'd see a doctor or nurse.
Bloodwork should be done at least every three months while on Imuran.
Good luck, I hope you get the pain resolved soon, that totally sucks!