Colonoscopy remains the reference examination for exploring the interior of the colon: it is the only one that allows both visualizing a lesion, biopsying it, and removing a polyp at the same time. Understanding how it actually takes place helps put fears into perspective that are often disproportionate to the reality of the exam.
1. The anesthesia consultation: an obligatory step, not a source of worry
Eight to ten days before the examination, a consultation with an anesthesiologist is mandatory. It allows you to take stock of current treatments, possible allergies, and to choose the most suitable modality: light general anesthesia or conscious sedation, the latter being increasingly offered. This is also an opportunity to ask any questions that are worrying.
| Step | When | What to do |
|---|---|---|
| Anesthesia consultation | 8 to 10 days before | Report treatments, allergies, history |
| Free diet residue | 2 to 3 days before | Avoid fruits, vegetables, whole grains |
| Taking a laxative | The day before (sometimes 2 days) | Drink the preparation fresh, well hydrate |
| Fasting | From midnight | Do not eat or drink anything before anesthesia |
2. Preparation: the least pleasant step, but the shortest
Colonic preparation consists of completely emptying the intestine to allow optimal visualization of the mucosa. It is based on two elements: a low-fiber diet (known as “residue-free”) the two to three days preceding the examination, and taking a powerful laxative in liquid form, generally the day before.
The taste of the laxative, often dreaded, improves significantly by drinking it very cold. Good hydration between doses limits inconvenience and facilitates effective preparation, an essential condition for a quality exam.
3. The day of the exam: shorter and more discreet than you imagineThe exam itself generally lasts between 10 and 30 minutes, under sedation or light anesthesia: the person feels no pain or discomfort during it. The gastroenterologist inserts a flexible tube fitted with a camera through the anus, allowing the entire colon to be explored. If a polyp is detected, it can be removed immediately using forceps or a snare, without additional steps.
After the examination, monitoring for approximately one hour is necessary while you recover from the effects of the sedation. An accompanying person must be present when waking up, as it is forbidden to drive or make important decisions on the day.
4. After the exam: minor side effects and results
Mild abdominal cramps and gas are common after the examination: they simply correspond to air being blown into the colon to facilitate visualization, and disappear quickly. A normal resumption of diet and activity is generally possible the next day.
The results of biopsies or analysis of removed polyps are generally transmitted by the treating physician or gastroenterologist within one to two weeks. This delay, sometimes a source of anxiety, simply corresponds to the time necessary for the anatomopathological analysis.
⚠️ To remember from a medical point of view
Colonoscopy carries few risks: serious complications (perforation, significant bleeding) remain rare and are subject to systematic safety procedures.
A “short” colonoscopy or without sedation may be offered in certain special cases; hypnosis is sometimes used as an alternative in cases of contraindication to anesthesia.
If the preparation proves insufficient and prevents correct visualization, a new cleaning or a new examination may be necessary, this is not a failure, but a precaution for the reliability of the result.
