I agree with the others. Call your GI and tell him you're increasing your meds before you do it. If you go ahead and increase, you may run out of medication and end up in a bad situation down the road. It's always good to let your GI know what's going on regardless, you may need to get in to see him/her. I try to keep mine updated on my condition every so often. Of course, I haven't been so lucky, I seem to always be battling a flare up or worried that I am going to flare. I agree with Kate22 about
rectal medication, whether you try Rowasa or Canasa (suppositories), they can be very helpful at stopping a flare.
To answer your original question though, I don't think every flare can be stopped. My last flare for example, was unstoppable. Even with prednisone, it took a LONG time to stabalize and I was rocky while tapering down. I don't think anything short of prednisone would have stopped that flare. Maybe Remicade or Humira but who knows. I had trouble getting off prednisone even after starting 6mp. I think in many cases, if you are aggressive from the first symptom, you may be able to stop a flare or buy yourself some time but not in every case. Some flares seem to be resistant to standard treatment. That brings me to another tought, you should probably get stool tests if you're suddenly experiencing symptoms. It may be due to a bug.