I don't think you can possibly get on and off prednisone in 2-3 weeks but I am not sure. I have been on prednisone only once, currently, and it's been quite a while. I initially thought I could get on and off in a short time but with the tapering, it has to take longer. I starteed at 40mg which I think is a lot but I guess it was necessary to get me out of my flare - it was quite intense. After one or two days at 40, I was much better. I think most people start around 40, maybe 30 if you are lucky and tapering at even 10mg a week it would be 3 weeks and most people don't taper that quickly. The reality is, you may have no choice in this, asacol/rowesa only helps so much. I tried increasng my asacol/canasa, no luck at all. I hope you have better luck with 5ASAs. It seems like if you were never on 5asa, maybe you would have luck getting out of a flare with them but if you are on them and you flare, you probably need more. I am scared for the day I flare again and I am a huge worrier so it's difficult to deal with.
Diagnosed with mild proctitis in March 2007: Treated with Canasa (as needed)
Relapse: August 08 - December 08: Began treating with Asacol 400mg (9/day) + Canasa 2x/day
Jan 09 Remission!! Canasa nightly + Asacol (9/day) + Probiotics + Iron
Relapse: Christmas 09 - Current, 5mg prednisone, 9 Asacol, Canasa - Improving