Sounds as if you need to find out if you're sensitive or allergic to the Canasa. Really, it's that cheap from Canada (I take it that you're in the US?) I have pretty good insurance but my co-pay for 30 Canasa is $120!
My experience is that inflammation anywhere in the colon, but especially in the rectum, takes a lot longer to really "heal" than we think. So, the Canasa stopped your bleeing in a few days.... but my guess is that the tissue would have taken another 3 weeks to really heal - or be on the way to healing. So.... my vote would be to go with taking them for 8 weeks.
I might be prone to tapering them at that point. A lot of us here, myself included, whose colitis goes throughout the colon, use the mesalamine enemas twice weekly as maintenance. Might there be benefit to doing that with Canasa.....?
Maybe someone with UP will chime in about
oral meds. I was put on oral meds when I was first diagnose with UP, and.... it became pancolitis after several years. I didn't start rectal meds until after my UC was up the left side and into the transverse. Might some Canasa have helped prevent that....? Who knows!
Welcome to the forum! You are a rider.....(That's the imagine I envision, of jumping....)