Asking to change medications?

ok, so i have had uc for 15 years...i went a span of 8 years with no symptoms.  For the past year or so, i have been having a minor flare, but with horrible arthritis. I have been on sulfasalizine for the full 15 years, and rowasa sporadically when needed. I was on humira for 2 months for the arthritis, it worked well but insurance won't cover it, so i have stopped that for now.....I have asked the gastro doc at least three times to switch medications to something newer and potentially will work better for my uc. He says to stay on the sulfasalizine because it is best for the arthritis, but even with increased dosages it didn't work for my uc or the arthritis. If some other medication like lialda, or colzadal would knocked the uc into complete remission then the arthritis would potentially decrease. Also, sulfasalizine decreases sperm count, and my wife and I are trying to have a baby.  He won't do it for some reason...he keeps harping on sulfasalizine is great for the arthritis....urrr, I just don't know what to do now. I just want to try a newer medication, but its going no where....should i just go to a new doc???

Yes, I probably would look into seeing a new doctor.  I recently went through something similar with my GI.  I like him very much as a person and was hesitant to change.  He is the only person who I have been to since I was diagnosed so there was the fact that I was familiar with him and his staff...however, he was not treating me as aggressively as I wished and was also not willing to try different methods or medications.  He also was not as knowledgeable about newer treatments as I would like.  So my primary care doctor set me up with a new and younger GI.  I am hoping for better longer term results with my new doctor.