About Mesalazine 5-Aminosalicylic Acid Derivative, Anti-inflammatory bowel agent. Mechanism of Action of Mesalazine Mesalazine exerts its anti-inflammatory action by inhibiting lipoxygenase enzyme. This will leads to decreased production of pro-inflammatory leukotrienes (LTB4) and 5-hydroxy eicosa tetra enoic acids (HETE) in the intestinal wall. It inhibits the production of inflammatory mediators like interleukin-1, tumor necrosis factor-alpha etc. Indications for Mesalazine 1.Ulcerative colitis 2.Crohn`s disease 3.Proctitis and Proctosigmoiditis (use only suppositories)