To prove that the efficacy and safety of Mucosta® (Rebamipide) is non-inferior to those of Cytotec® (Misoprostol), in terms of prevention of NSAID-induced gastric ulcer.

Inclusion Criteria:

1. Signed written informed consent after being informed of the clinical trial
2. Males or females 19 years of age
3. Intake of any brand of NSAIDs in more than half of daily dose for at least the previous 4 weeks.

Exclusion Criteria:

1. Necessary to proceed in concomitant treatment with epileptic medications, anti-chollinergics, prokinetics, sucralfate
2. Presence or history of allergic drug reaction to the following medications; rebamipide, Misoprostol, NSAIDs designated to the protocol