I was also started on 40 mg of prednisone for my first major flare in a long time 5 weeks ago. I am currently tapered down to 30 mg. I was on 40 mg for three weeks! Too long, but my colonoscopy (my very first one) looked bad, as my GI said. I expect to be on prednisone for a total of 10 weeks. For me, the prednisone took away my symptoms in about 10 days. Prior to that I also had B in my stools every time (4 x a day). And then one day my bms became normal. I think you should give it more time. The side effects are awful, but, you're right, prednisone works.
Diagnosed with left-sided UC 2/08, originally diagnosed 20 years ago
Prednisone 30 mg (5th week)
SCD Diet - It really works!
Assorted probiotices - 7/day