All are true about the newer preparations of 5-ASA to treat inflammatory bowel disease, EXCEPT:

Asacol is an enteric coated form of mesalamine. The disintegration of Asacol is variable, with complete breakup of the tablet occurring in many different pas of the gut ranging from the small intestine to the splenic flexure; it has increased gastric residence when taken with a meal. Also know: Pentasa is another mesalamine formulation that uses an ethylcellulose coating to allow water absorption into small bowel. A once-a-day formulation of mesalamine [Multi-Matrix System (MMX) is designed to release mesalamine in the colon. As a general rule, 5-ASA agents act within 2-4 weeks. Ref: Harrison, Edition-18, Page-2489