I had a month or so on Entecort (
budesonide here in England) but had a severe rectal haemorrhage
and was hospitalised on IV steroids and needed blood transfusions. I don't think my gastro in England, who prescribed it, at the time realised that Entecort only works in the small intestine, and I had Pan Crohn's Colitis. As I had stopped prednisone to go onto budesonide, I had no protection in the colon, hence the flare.