An agent derived from sulfasalazine, an antiinflammatory agent. Mesalamine may reduce inflammation through inhibition of cyclooxygenase and prostaglandin production. Following rectal or oral administration, only a small amount of mesalamine is absorbed; the remainder, acting topically, reduces bowel inflammation, diarrhea, rectal bleeding and stomach pain. Mesalamine works as an antiinflammatory agent in treating ulcerative colitis and Crohn's disease through a topical effect on the inflamed bowel. It (NCI04)