Aspirin, the salicylic ester of acetic acid is one of the most common drugs in use today. Although, low dose aspirin has many uses, several previous studies have proved that, low doses of aspirin are associated with upper gastrointestinal complications, even hematemesis, melena, and perforation. Our study included 32 patients who were received low dose aspirin. The indications for low dose aspirin therapy were cerebrovascular stroke, cardiovascular diseases, and D.V.T. The patients were divided according to their ages into 4 groups .The patients were, also divided according to duration of aspirin therapy into 4 groups.Males represent 59.375 %, females represent 40.625% All patients were received doses about 150 mg /day. All patients were subjected to endoscopical examination using Olympus GIF 240 Video-scope.There was a significance between the esophageal , stomach and duodenal findings by endoscopy and the duration of aspirin therapy ( P value <0.05 ) .Our study also proved that the gastrointestinal complications occurred during the first 6 months of treatment with low dose aspirin .An explanation of this phenomenon is the development of tolerance or adaptation of the gastrointestinal mucosa to the toxic effect of aspirin . This adaptation seems to take place around 2 months ( according to the previous studies ) and is definitely completed by 6 months (according to our study)