This is a phase IV clinical study to evaluate the preventive effectiveness of NSAID-Associated Gastroduodenal Injury. The study is consisted of multi-center, doubleblind, active-controlled, stratified randomized, parallel group. A tablet of DA9601, Cytotec (200ug of Misoprostol), Acrofen (100mg of Aceclofenac) will be assigned randomly to the subjects for four weeks.