Colonoscopy (lower endoscopy)

Colonoscopy is one of the most accurate and informative methods for examining the colon and rectum. It allows the doctor to examine the intestinal mucosa in detail and detect polyps, inflammatory changes, ulcers, sources of bleeding, tumors, and other abnormalities early on—conditions that are not always detectable using other diagnostic methods.

Colonoscopy is not only a diagnostic procedure but, in many cases, also a therapeutic one. During the examination, the doctor can, if necessary, take tissue samples (biopsies) for microscopic examination, as well as remove polyps or perform other endoscopic procedures. Taking a biopsy is usually quick and painless. In the case of larger or more complex polyps, a separate, pre-planned therapeutic procedure may be necessary.

During the examination, a flexible endoscope with high-resolution optics is inserted into the large intestine through the anus. This allows the doctor to view the large intestine up to the cecum and, if necessary, the terminal portion of the small intestine. Images from the examination are documented, saved, and attached to the report that the patient receives after the procedure.

Colonoscopy, when performed by an experienced specialist using modern equipment, is a safe and low-risk procedure. However, as with any medical procedure, colonoscopy can very rarely lead to complications, such as bleeding after a biopsy or polyp removal, damage to the intestinal wall, or reactions related to sedation. Before the procedure, the patient is informed about the course of the examination, its benefits, and potential risks.

Colonoscopy is typically performed under intravenous sedation, which helps ensure the patient’s calm and comfort. During sedation, an anesthesiologist or anesthesia team administers short-acting medications to make the procedure as comfortable as possible and ensure the patient remembers little or nothing of it. This is not general anesthesia; the patient usually breathes on their own, but vital signs are continuously monitored during the procedure.

When is a colonoscopy necessary?

A colonoscopy is recommended if there is:

• blood or mucus in the stool;
• a change in stool consistency or frequency—persistent diarrhea, constipation, or a shift in these symptoms;
• pain or discomfort during bowel movements;
• unexplained weight loss, fatigue, weakness, or lack of energy;
• iron-deficiency anemia or anemia of unknown cause;
• a positive fecal occult blood test;
• suspected inflammatory bowel disease or the need for follow-up;
• a family history of colorectal cancer or intestinal polyps;
• previously diagnosed intestinal polyps requiring a follow-up colonoscopy;
• a need for colorectal cancer screening as recommended by a doctor.

How long does the procedure take?

The colonoscopy itself usually lasts about 20–60 minutes, depending on the anatomy of the bowel, the quality of preparation, and whether additional procedures, such as a biopsy or polyp removal, are performed during the procedure.

The total time spent at the clinic is usually about 1.5–2 hours, as a short observation and recovery period is required after sedation.

After the examination

After a colonoscopy, the patient may go home the same day if they feel stable and the medical staff permits it. If the procedure was performed under sedation, for 24 hours after the examination, the patient must not drive a vehicle, operate machinery, make legally or financially significant decisions, or consume alcohol. It is recommended that an adult accompany the patient home after the procedure.

After the examination, you may experience temporary bloating, a sensation of gas, or mild discomfort, which usually resolves on its own. If a biopsy or polyp removal was performed during the colonoscopy, the doctor will provide individual instructions regarding your post-procedure regimen, receiving results, and necessary follow-up.

You should contact your doctor immediately or seek emergency care if you experience severe or worsening abdominal pain, fever, significant rectal bleeding, dizziness, fainting, or a significant deterioration in your well-being after the procedure.