I got this off a website. Hope it helps :)
How does Pentasa differ from Asacol
Both Pentasa and Asacol are prescription forms of mesalamine. The difference between Asacol and Pentasa is in the outer chemical coating. Oral Pentasa has a unique formulation. The active ingredient is contained in coated microgranules, which enables a prolonged release of the active substance throughout the intestinal tract, from duodenum to the rectum. Therefore the Pentasa preparation is more useful for Crohn's patients who often have inflammation of the small intestine. The average small bowel transit time is approximately 3-4 hours in healthy volunteers.
Asacol is a delayed release enteric-coated tablets which generally releases the active ingredient only in the colon. While there are always clinical exceptions, Asacol is generally suitable for patients with colitis only (ulcerative colitis or Crohn's colitis), but not disease involving the small intestine.
Diagnosed with UC in 2006
Salofalk 2gms twice a day for maintance
Salofolk 4gms twice a day during flares
Betnesol retention enemas for flares - have been on back order so not available until Feb
Pentasa enemas and supps when first diagnosed
Asacol 2.5gms twice daily
Cortifoam enemas nightly for 3 weeks, then everyother night for 4 weeks