Most current drug delivery systems in the treatment of ulcerative colitis and Crohn's disease release the active drug at the least effective location for treatment. The pharmaceutical industry has been developing different delivery systems for Multi-Matrix System (MMX) mesalamine for the treatment of Crohn's disease and ulcerative colitis. The new oral mesalamine formulation is a once-daily MMX tablet that delivers the mesalamine to the colon, making it most useful in the treatment of ulcerative colitis. The MMX coating matrix and coating system begin dissolution in the final portion of the ileum. This type of oral formulation may make MMX a preferred agent over other oral mesalamine and mesalamine-prodrug formulations that release the drug proximally in the gastrointestinal tract. Unlike previous formulations, it can be administered once daily for the treatment of ulcerative colitis.