The colonoscopy cleansing pulling a dozen times or yellow water indicates that the bowel preparation is incomplete, which may be related to poor dietary preparation before the examination, drinking too little water, insufficient medication, combined with intestinal masses and other reasons, as follows. 1. Poor dietary preparation before bowel cleansing: if you eat too much solid food the day before the colonoscopy or before taking medication, it may lead to the situation of yellow water after a dozen times. 2. Drinking too little water: If you drink too little water during bowel cleansing, it may also lead to incomplete bowel preparation, at this time, you can accelerate bowel excretion by drinking more water. 3. Insufficient medication: Before doing colonoscopy, it is generally necessary to take laxatives such as compound polyethylene glycol electrolyte bulk to promote excretion, if the amount of medication is not enough, there may be a dozen times or yellow water pulling situation. 4. Combined with intestinal masses: if combined with intestinal polyps, intestinal tumors, intestinal infections and other diseases, the patient may be due to swelling blockage of the intestinal tract or intestinal infections are more serious, and there is a situation of pulling a dozen times or yellow water. There are many other reasons that cause colonoscopic bowel cleansing pulling a dozen times or yellow water, it is recommended to take appropriate measures under the guidance of the doctor to achieve the desired bowel preparation effect.