Has your GP mentioned the possibility of labyrinthitis? I've had labyrinthitis for 6+ weeks now, it involves the inner ear being inflamed, which in turn causes dizziness/vertigo and it can also affect the ability to hear. I haven't had ringing in my ear but I had sort of a crackling in my ear which started shortly before the dizziness did (I'm about 80% better now, just some residual dizziness - I was told it sometimes takes months to fully recover from this type of thing). My GP said he highly doubts that it's related to my IBD or any of my medications (I'm not on Imuran, for what it's worth), and it seems to just be one of those things that happens sometimes and is often due to a virus (has your daughter had a cold or anything like that just prior to the ringing & dizziness? My GP said sometimes a person will have a cold and then a week or two later the virus will actually have moved in to the inner ear which causes the labyrinthitis). I hope your daughter feels better soon and that it's just something minor and not related to her meds! Good luck with the blood work.