Colonoscopy is currently a widely used examination method worldwide, which can detect lesions in the colon and terminal ileum, but when it comes to colonoscopy many people feel scared and intimidated, so how do we prepare our intestines so that we can get a smooth colonoscopy? Choice of bowel cleanser Polyethylene glycol (PEG): PEG solution is an isotonic solution that does not affect the absorption and secretion of the intestine, and therefore does not cause water-electrolyte disorders, and its safety and effectiveness have been well established. Other laxatives: including magnesium citrate + sodium sulfate, hypertonic magnesium sulfate solution, senna, mannitol, bisacodyl, etc. Senna achieves similar effects to PEG, but is poorly tolerated by patients and can lead to complications such as abdominal pain. High doses of bisacodyl also achieve satisfactory cleansing, but can lead to abdominal cramps. Mannitol may lead to explosion under electrothermal manipulation of the endoscope. In summary, polyethylene glycol (PEG) is generally recommended as the first-line drug for intestinal preparation, such as Hershey and Hengkang Zhengqing. The following is an example of polyethylene glycol (PEG) to talk about how to prepare the intestine: How to prepare the intestine? For morning examination, fast or eat liquid diet (no dregs diet, such as clear soup, white sugar water, honey water, etc.; dairy products, such as milk, soy milk, coconut milk, thick soup, etc.) at dinner in the evening before the examination day; for afternoon examination, fast or eat clear liquid diet at breakfast on the examination day Dosing time: one dosing time point: for morning examination, start to take the bowel cleanser at 6-7 pm before the examination day and finish within 2 hours. For the afternoon examination, start taking the purgative at 8-9 am and finish within 2 hours. Split dose time point: i.e., the first dose is given the night before and completed within 2 hours. The second dose is administered on the morning of the colonoscopy, 4-6 hours before the start of the examination, and is completed within 2 hours. The first dose is administered the morning of the colonoscopy, 4-6 hours before the start of the examination, and the second dose is administered 2 hours before the start of the examination. 3. One-time dosing method: He Shuang: Dissolve 1 bag (137.15 g/bag) in 2000ml of warm water (equivalent to 4 bottles of mineral water), stir well and drink it within 2 hours (250ml every 15 minutes, equivalent to half a bottle of mineral water). Hengkang Zhengqing: Take two boxes of this product (containing A, B and C sachets), pour each packet of powder in the box into a cup (bottle) with a scale, add warm boiled water to 1500ml, stir to dissolve completely, then take. Drink for the first time until you feel full, then drink the rest of the liquid as much as you can stand, and finish it within 2 hours. Drink another 1500ml of warm water. (First dose) Dissolve 1 sachet (68.56 g/bag) in 1000 ml of warm water (equivalent to 2 bottles of mineral water) the night before the examination, stir well and drink it within 2 hours (250 ml every 15 minutes, equivalent to half a bottle of mineral water). (Second dose) Dissolve the other bag (68.56 g/bag) and Sharp all in 1000 ml of warm water (equivalent to 2 bottles of mineral water) 4-6 hours in advance on the day of examination, stir well and drink it within 2 hours (take 250 ml every 15 minutes, equivalent to half a bottle of mineral water). Hengkang Zhengqing: (First dose) Dissolve one box of this product in 1000ml of warm water the night before the examination, stir well, and take 250ml every 10-15 minutes, if there is serious abdominal distension or discomfort, slow down or suspend taking it, and continue taking it after the symptoms disappear, and finish it in 2 hours. (Second dose) Add another box of Hengkang Zhengqing to 2000ml of warm boiled water 4-6 hours in advance on the day of examination and continue to take 250ml orally every 10-15 minutes. 4. During the patient’s dose, walk back and forth and gently rub the abdomen to speed up excretion. Observe the end point: clear water-like stool; if still not dry, drink another 1000 ml of water. 6. 6. strict fasting should be observed after the bowel cleanse. Caution: 1) When choosing PEG as a purgative, it is not advisable to take other oral medications 1 h before taking laxatives. 2) For constipation, eat a semi-liquid diet (white porridge, soft noodles, etc.) two days before the examination and abstain from fiber diet (green vegetables, fruits, etc.). 3) Painless colonoscopy: ①Ensure that you fast for 6 hours or more before the examination. ②The examination will take about 15 minutes on average, sometimes it may take a little longer due to individual differences or abnormalities in the large intestine. ③After the examination, you should tell your doctor promptly for further treatment if you have obvious abdominal pain, bloating, dizziness and other symptoms. ④There are certain risks in the examination. For your safety, elderly people over 60 years old should have ECG examination first. 3. Warm tips Implement colonoscopy appointment time. You must sign the informed consent form before the examination and be accompanied by family members on the examination day. If you have relevant examination reports and previous colonoscopy reports, please bring them with you for the doctor’s reference.