Dimethicone is a medication that eliminates mucus bubbles in the intestines and is usually taken 3 to 4 hours before the colonoscopy. There are a lot of bacteria in the intestines, and after drinking a laxative before the colonoscopy, a lot of air bubbles will be produced in the intestines. When dimethicone is taken 3 to 4 hours before the colonoscopy, it can effectively remove the bubbly mucus in the stomach so that the bowel is cleaner and clearer during the colonoscopy. Some patients may have adverse reactions such as stomach upset, diarrhea and vomiting when taking dimethylsiloxane oil, and those who are allergic to this product are prohibited from taking it. After doing colonoscopy, patients should be prohibited from fasting and water within 6 hours, until after you can eat, you need to eat light, easy to digest liquid food, 3 days before you can gradually resume a normal diet. When patients need to take dimethylsilicone oil before doing colonoscopy, it is recommended to do so under the guidance of a doctor, and not to use the drug on their own, so as not to produce the risk of using the drug.