Colonoscopy is generally a safe procedure. However, as with any medical procedure, there are some potential risks and complications. These risks are generally rare but can occur during or after the procedure and may include: Bleeding; Infection; Outpouching of the colon wall (diverticula formation); Severe abdominal pain; Adverse reactions to sedatives or anesthetics used during the procedure; Tearing of the colon or rectum wall (perforation); Serious complications such as cardiovascular events, particularly in individuals with heart or blood vessel disease.