cita, how much imuran are you going to start on?
also keep in mind that imuran could take 3-6 months to work. looks like you are on pred, i also used pred as a bridge to imuran, i weaned off the pred after 6 weeks on imuran, had a bit of bleeding so my gi dr upped my imuran from 50 to 100 (back in july/august).
with imuran, i had some nausea and stomach pains for the first few weeks. take the imuran after you have eaten, not on an empty stomach. also, i stopped taking my multivitamin and the stomach pains stopped. i will even tell you that 6 weeks into imuran, i had a gallbladder attack and in august had my gallbladder out, all with no problems with my uc. Now, 6 months later on imuran, i feel great, no side effects. every once in while i have some blood, so i still use rectal meds.
good luck to you with imuran!