High blood pressure (<160/100mmHg) can do painless colonoscopy, higher than 160/100mmHg is not recommended painless examination. Painless colonoscopy is performed under general anesthesia. Before anesthesia, the anesthesiologist needs to assess the patient's vital signs and condition to formulate the most appropriate anesthesia plan. Regardless of whether the patient has high blood pressure in the past or not, when the blood pressure is higher than 160/100mmHg before the examination, it is not recommended to carry out colonoscopy immediately, and it is necessary to use antihypertensive medication or wait until the blood pressure drops after resting before carrying out the colonoscopy. If the blood pressure is higher than 160/100mmHg, the risk of cerebral hemorrhage and cardiac arrhythmia will be increased. If you have high blood pressure, you should follow your doctor's instructions to perform painless colonoscopy.