Helicobacter pylori infection and non-steroidal anti-inflammatory drugs (NSAID) have been accepted as major causes of upper gastrointestinal (GI) ulcers and bleeding. As patients with Helicobacter pylori infection have decreased, upper GI disorders related to NSAID have been relatively increasing. Among patients taking low-dose aspirin, the prevalence of upper GI ulcers is 10-40% and aspirin increases the risk of upper GI bleeding up to 2-fold. Among patients taking nonaspirin NSAID, the prevalence of upper GI ulcers is around 20% and nonaspirin NSAID increases the risk of upper GI bleeding up to 4- to 6-fold. Since the prevalence of GI disorders related to NSAID is very high, endoscopic examination might be considered to monitor GI lesions for patients taking NSAID.