I was on 5ASA's for 7 years and can no longer take them, I have close to what you have, have only the first 30cm of my colon affected. I went cold turkey off the 5ASA's and had the worst flare ever (going 25+ times a day w/all the horrible UC side effects). I am on pred for a different reason and that took a long time to help me (2 mos w/my UC), I think the hydrocortisone enema's really got my flare under control, though that took a couple of weeks.
I have only been on Azathioprine (generic of Imuran) for about a month. The side effects I think I have (I am on so many different meds) gotten from it is being tired, but taking all the AZA at night has helped my groggines in the am, also my leg hair has pretty much stopped growing. I have not had any hair loss on my head, I have been taking 800mg of folic acid a day (I think that is supposed to help???).
The Imuran i'm told can take 3-6 mos to work, so my GI was going to put me on remicade to help stop the flare until the Imuran started to work but since I am doing really well right now b/c of the pred and hydrocoritsone e's (1-2 bm's a day almost fully formed, no D, B, mucous and cramping), that is on hold indefinitely.
I was really upset when I had to stop the 5ASA's b/c they worked so well for my UC, but unfortunately, no choice and I just want to be well again and have a few solid months under my belt (so to speak).
UC Diagnosed March 2000 (30 cenitmeters)
Azathioprine 150mg 1xday nightly;Hydrocortisone enemas 1xday;Calcium and Vit D 500mg 3xday, Multi Vit, Folic Acid 400mg 2xday, Potassium 600mg 2xday, Probiotics.
Minimal Change Disease (Kidney Disorder) Diagnosed Sept 2007
Prednisone 60/40mg alt days 1xday, Simvastatin 20mg 1xday, Diovan 80mg 2xday. Fosomax 70mg 1xweek. MCD may be from hypersensitivty to 5ASA drugs.