Upper gastrointestinal endoscopy (esophago–gastro–duodenoscopy or EGD) is one of the most common diagnostic and therapeutic methods of upper gastrointestinal diseases .One limitation of the method is, however, the presence of air bubbles and foam in stomach and duodenum, which leads to decreased diagnostic accuracy, prolonged endoscopy time, and decreased patient’s tolerance. Therefore, gastric and intestinal preparation prior to endoscopy is necessary for the removal of the bubbles. Currently, except fasting prior to endoscopy, no standard method has been recommended for prior EGD preparation.Simethicone is a detergent, which is a chemical mixture of dimethyl polysiloxane and silica gel and it helps in reduction of foam and air bubbles