Why can’t I eat before surgery?

For your colonoscopy, it’s important that your colon is completely clear. There’s also a risk of aspiration, which means breathing foreign objects, like food or saliva, into your lungs. This can occur because the anesthetic for surgery can impair your body’s ability to stop the contents of your stomach from entering your lungs. Depending on the surgeon and the type of colonoscopy prep, the patient may take their last dose of medication anywhere from 4-8 hours before arrival to facility for the procedure. These details are specific to the patient’s need and ordering physician.