Olsalazine
Olsalazine is a prodrug of mesalamine (5-Aminosalicylic acid; 5-ASA) with anti-inflammatory activity. Unabsorbed olsalazine passes through gastrointestinal tract and is cleaved by azoreductases, produced by microflora in colon, into 2 active molecules of 5-ASA. 5-ASA exerts its anti-inflammatory action locally by inhibiting cyclooxygenase and lipoxygenase activities, thereby reducing the production of prostaglandins and leukotrienes. In addition, mesalamine may act as a scavenger of reactive oxygen free radicals.