Chronic NSAIDs Therapy and Upper Gastrointestinal Tract – Mechanism of Injury, Mucosal Defense, Risk Factors for Complication Development and Clinical Management

New Advances in the Basic and Clinical Gastroenterology 150 100.000 patients were admitted every year for NSAIDs related adverse events, resulting in about 15000 deaths (Weil et al., 2000;Ofman et al., 2002).Non-selective NSAIDs (nsNSAID) inhibit both cyclooxigenase-1 (COX1) and cyclooxigenase-2 (COX2).These two enzyme have different roles in the cell and, in particular, COX1 mediates prostaglandin (PG) secretion which is one of the upper GI protective mechanisms.That is why, with the aim of reducing NSAIDs related upper GI toxicity, selective COX2 inhibitors (coxibs) were developed in the last decade.Coxibs weakly inhibit COX1 and a reduced relative risk of developing upper GI injury was demonstrated in clinical trials in patients receiving coxibs.