What information are you looking for? I've used all 3 of those before. Unfortunately, asacol was fairly expensive too in comparison to pentasa and canasa. I was on asacol for a few years until it stopped working for me (or my doctor thought it did). Sulfasalazine was the cheapest out of all of these and I was on that when I was first diagnosed till that stopped working. Biggest thing of all is to find what works for you though...