Doing colonoscopy and taking laxatives without response is often related to improper medication taking methods, low drug sensitivity, and intestinal obstruction. Common situations and related suggestions are as follows: 1. Inappropriate medication taking method: Inadequate dosage of laxatives, time not reaching the standard, not drinking a lot of water after drinking laxatives, etc. can lead to no response after taking medication. Patients should pay attention to take medicine according to the correct method of taking medicine, that is, to follow the doctor’s instructions to use the correct amount of medicine, wait for sufficient time for the effect of the medicine to play, and should pay attention to drink a lot of water after taking the medicine; 2, low drug sensitivity: because of the patient’s personal physical problems, such as nerve insensitivity, body tolerance, resulting in low sensitivity to laxatives, so there is no response to laxatives taken before the colonoscopy. The dose of laxatives can be increased under the guidance of the doctor to improve the efficacy, but not to increase the dose on their own to avoid adverse consequences; 3, intestinal obstruction: if you have not been relieved of stool after drinking laxatives and vomiting symptoms, the possibility of intestinal obstruction should be considered, such a situation can not continue to take laxatives, should promptly go to the hospital for relevant examination and take treatment to lift the intestinal obstruction.