BACKGROUND: Many endoscopists generally use topical pharyngeal anesthesia as a premedication for upper gastrointestinal endoscopy. However, the use of topical pharyngeal anesthesia for upper GI endoscopy has been debated since its inception. The purpose of this study was to compare the effect of no premedication to the effect of a lidocaine premedication. METHODS: One hundred consecutive examinees scheduled for diagnostic upper endoscopy, divided into two group 50, were randomly assigned to receive topical lidocaine spray or without. The test group involved subjects not using topical pharyngeal anesthesia and the control group involved subjects using it without sedation. The collected Data included intubation time (seconds), procedure time (minutes), pulse rate, blood pressure, the difficulty of the endoscopy (VAS), anxiety (STAI), and discomfort. Examinees were also asked whether they would agree to another endoscopy if their doctor thought it was medically necessary. RESULTS: In the response to the amount of cough, belching, bloating or the degree of difficulty in endoscopic procedure, there was no statistically significant difference between the test group and the control group. The intubation time was significantly different comparing the no-premedication group versus lidocaine premedication group. However, the procedure time was not significantly different. In the normotensive group, the changes of systolic blood pressure during endoscopy were significantly higher in the test group than in the control group. CONCLUSION: Evaluating all variables, there was no statistically significant difference between the test group and the control group.